Template:Citation - Wikipedia (original) (raw)

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The Citation, Cite, or cite template generates a citation for a book, periodical, contribution in a collective work, or a web page. It determines the citation type by examining which parameters are used. As with other citation templates, this template can be used either in a footnote (between <ref>...</ref> tags) or in a section that lists sources. This template uses the same Lua code as citation style 1 (CS1) templates with parameters to change the displayed format to citation style 2 (CS2).

If the correct parameters are used, this template produces output identical to that of the Cite templates, such as {{Cite book}} and {{Cite web}}, with one important exception: By default, this Citation template uses commas in places where the Cite templates use periods (full stops) by default; either type of template can use periods (full stops) or commas by using an optional parameter.

Regardless of which citation templates are used or even if none are used at all, all citations should have the same format throughout an article in the saved, rendered text.

Notes:

• All parameter names must be lowercase.
• Invisible unicode space characters (see list) will return an error message. Non-intentional invisible characters should be removed; intentional ones should be replaced with their corresponding HTML entity (e.g. ​).

Simple citations

This section covers the most commonly used parameters. You can copy the horizontal form or vertical form below and then add in extra parameters from the full list. Spacing and ordering of the parameters within the template is irrelevant and does not affect the final, rendered text.

{{Citation |last= |first= |year= |title= |publisher= |publication-place= |page= |url= |access-date=}}

{{Citation | last = | first = | year = | title = | publisher = | publication-place = | page = | url = | access-date = }}

• last: The author's surname or last name. Don't use with the author parameter.
• first: The author's first or given name(s).
• year: Year of authorship or publication. Mandatory for use with links from Template:Harvard citation, unless |date= specifies both month and year.
• title: Title of the work. Mandatory for web references.
• publisher: The name of the publisher. Omit terms such as Publishers, Co., Inc., Ltd., etc., but retain the words Books or Press. Not normally included where the publication is a periodical which has its own Wikipedia article (e.g. Newsweek, Billboard).
  • publication-place (or place or location): The city of publication. If more than one town/city is listed on the title page, give the first one or the location of the publisher's head office. Omit when the publication is a periodical whose name specifies the location (e.g. The New York Times, The Times of India)
• page: For use when one page is cited. Adds "p." before the page number. Do not use with pages.
• url: A url of an online location where the item can be found. If the url includes double quotes, these must be encoded as "%22".
  • access-date: Date[n 1] when the url was accessed.

Example

Full citation parameters

These can be used for all types of publication. All are optional and indentation is used simply to group related items — these may be mutually exclusive where indicated. Some hyphenated names can also be placed without hyphens.

{{Citation | last1 = | first1 = | author-link1 = | last2 = | first2 = | author-link2 = | display-authors = | author-mask1 = | author-mask2 = | collaboration = | date = | year = | orig-date = | location = | editor-last1 = | editor-first1 = | editor-link1 = | editor-last2 = | editor-first2 = | editor-link2 = | display-editors = | editor-mask1 = | editor-mask2 = | title = | script-title = | trans-title = | title-link = | url = | url-access = | format = | department = | website = | script-website = | trans-website = | type = | series = | language = | interviewer-last1 = | interviewer-first1 = | interviewer-link1 = | interviewer-last2 = | interviewer-first2 = | interviewer-link2 = | display-interviewers = | interviewer-mask1 = | interviewer-mask2 = | translator-last1 = | translator-first1 = | translator-link1 = | translator-last2 = | translator-first2 = | translator-link2 = | display-translators = | translator-mask1 = | translator-mask2 = | others = | name-list-style = | edition = | publication-place = | publisher = | publication-date = | minutes = | time-caption = | time = | page = | pages = | at = | no-pp = | arxiv = | asin = | asin-tld = | bibcode = | bibcode-access = | biorxiv = | citeseerx = | doi = | doi-access = | doi-broken-date = | eissn = | hdl = | hdl-access = | isbn = | ismn = | issn = | jfm = | jstor = | jstor-access = | lccn = | medrxiv = | mr = | oclc = | ol = | ol-access = | osti = | osti-access = | pmc = | pmc-embargo-date = | pmid = | rfc = | sbn = | ssrn = | s2cid = | s2cid-access = | zbl = | id = | url-status = | archive-url = | archive-format = | archive-date = | access-date = | via = | quote-page = | quote-pages = | quote = | script-quote = | trans-quote = | mode = | ref = | postscript = }}

Parameters

Syntax

Nested parameters rely on their parent parameters:

• parent
• OR: _parent2_—may be used instead of parent
  • _child_—may be used with parent (and is ignored if parent is not used)
  • OR: _child2_—may be used instead of child (and is ignored if parent2 is not used)

Where aliases are listed, only one of the parameters may be defined; if multiple aliased parameters are defined, then only one will show.

By default, sets of fields are terminated with a comma (,).

COinS

This template embeds COinS metadata in the HTML output, allowing reference management software to retrieve bibliographic metadata. See Wikipedia:COinS. As a general rule, only one data item per parameter. Do not include explanatory or alternate text:

• use |date=27 September 2007 not |date=27 September 2007 (print version 25 September)

Use of templates within the citation template is discouraged because many of these templates will add extraneous HTML or CSS that will be included raw in the metadata. Also, HTML entities, for example  , –, or  , should not be used in parameters that contribute to the metadata.

COinS metadata is created for these parameters

Note: This table of metadata is displayed in the documentation of all Citation Style 1 templates. Not all of these parameters are supported by every CS1 template. Some of these parameters are mutually exclusive, some are aliases of another parameter, and some require other parameters to be present. A full list of this template's supported parameters, their aliases, and their dependencies is shown in the Usage section near the top of this documentation page.

• |periodical=, |journal=, |newspaper=, |magazine=, |work=, |website=, |encyclopedia=, |encyclopaedia=, |dictionary=
• |chapter=, |script-chapter=, |contribution=, |script-contribution=, |entry=, |script-entry=, |article=, |script-article=, |section=, |script-section=
• |title=, |script-title=, |book-title=
• |publication-place=, |place=, |location=
• |date=, |year=, |publication-date=
• |series=, |version=
• |volume=, |issue=, |number=
• |page=, |pages=, |at=, |quote-page=, |quote-pages=
• |edition=
• |publisher=, |institution=
• |url=, |chapter-url=, |contribution-url=, |section-url=
• |author-last=, |author-last#=, |author#-last=, |author-surname=, |author-surname#=, |author#-surname=, |last=, |last#=, |surname=, |surname#=, |author=, |author#=, |subject=, |subject#=, |host=, |host#=
• |author-first=, |author-first#=, |author#-first=, |author-given=, |author-given#=, |author#-given=, |first=, |first#=, |given=, |given#=
• |degree=
• |arxiv=, |bibcode=, |biorxiv=, |citeseerx=, |doi=, |eissn=, |eprint=, |hdl=, |isbn=, |issn=, |jfm=, |jstor=, |lccn=, |message-id=, |mr=, |oclc=, |osti=, |pmc=, |pmid=, |rfc=, |ssrn=, |s2cid=, |zbl=

What's new

What's new or changed recently

Deprecated

Deprecated CS1/CS2 parameters

Recently removed CS1/CS2 parameters | Removed parameter | Replace with | Date | Note | | | | | ----------------- | ------------ | --------- | ---------- | --------- | ----------- | | | |authors= | |lastn= / | firstn=, | authorn=, | vauthors= | August 2024 | |

Description

Authors

• last: Surname of a single author. Do not wikilink—use author-link instead. For corporate authors or authors for whom only one name is listed by the source, use last or one of its aliases (e.g. |author=Bono). Aliases: surname, author, last1, surname1, author1.
  • author: this parameter is used to hold the name of an organizational author (e.g. a committee) or the complete name (first and last) of a single person; for the latter, prefer the use of |first= and |last=. This parameter should never hold the names of more than one author. Supports accept-this-as-written markup. Do not use italics in this field, as doing so produces corrupt metadata.
  • first: Given or first names of author; for example: Firstname Middlename or Firstname M. or Firstname M. Sr. Do not wikilink—use author-link instead. Aliases: given, first1, given1. Requires last; first name will not display if last is empty. Use generational and regnal suffixes only in accordance with MOS:JRSR and use honorifics (including Dr., Sir, and similar) only in accordance with MOS:HON.
  • OR: for multiple authors, use last1, first1 through lastn, firstn, where n is any consecutive number for an unlimited number of authors (each firstn requires a corresponding lastn, but not the other way around). See the display parameters to change how many authors are displayed. Aliases: surname1, given1 through surnamen, givenn, or author1 through authorn. For an individual author plus an institutional author, you can use |first1=... |last1=... |author2=....
  • author-link: Title of existing Wikipedia article about the author—not the author's website; do not wikilink. Aliases: author-link1, author1-link, authorlink.
  • OR: for multiple authors, use author-link1 through author-linkn. Aliases: author1-link through authorn-link.
  • name-list-style: accepts a limited list of keywords as value; when set to amp, ampersand, or &, inserts an ampersand between the last two names in a name list; when set to and, inserts the conjunction 'and' between the last two names of a name list; when set to vancdisplays name lists in Vancouver style when the lists use the last/first forms of name parameters.
• vauthors: comma-separated list of author names in Vancouver style; enclose corporate or institutional author names in doubled parentheses. End with etal if appropriate:
  |vauthors=Smythe JB, ((Megabux Corp.)), etal
  • author-link and author-mask may be used for the individual names in |vauthors= as described above
• authors: deprecated Free-form list of author names; use of this parameter is discouraged because it does not contribute to a citation's metadata; not an alias of last.
• contributor-last: (book cites only) surname of the author of contribution (which is required). Aliases: contributor-surname, contributor1, contributor1-last, contributor-last1. Supports accept-this-as-written markup.
  • contributor-first: Given or first names of contributor. Do not wikilink—use contributor-link instead. Aliases: contributor-given, contributor1-first, contributor-first1.
  • OR: for multiple contributors, use contributor-last1, contributor-first1 through contributor-lastn, contributor-firstn where n is any consecutive number for an unlimited number of contributors (each contributor-firstn requires a corresponding contributor-lastn, but not the other way around). Aliases: contributor1-last, contributor1-first through contributorn-last, contributorn-first, or contributor1 through contributorn.
  • contributor-link: Title of existing Wikipedia article about the contributor—not the contributor's website; do not wikilink. Aliases: contributor-link1, contributor1-link.
  • OR: for multiple contributors, use contributor-link1 through contributor-linkn. Aliases: contributor1-link through contributorn-link.
• translator-last: Surname of translator. Do not wikilink—use translator-link instead. Aliases: translator-surname, translator1, translator1-last, translator-last1. Supports accept-this-as-written markup.
  • translator-first: Given or first names of translator. Do not wikilink—use translator-link instead. Aliases: translator-given, translator1-first, translator-first1.
  • OR: for multiple translators, use translator-last1, translator-first1 through translator-lastn, translator-firstn, where n is any consecutive number for an unlimited number of translators (each translator-firstn requires a corresponding translator-lastn, but not the other way around). Aliases: translator1-last, translator1-first through translatorn-last, translatorn-first, or translator1 through translatorn.
  • translator-link: Title of existing Wikipedia article about the translator—not the translator's website; do not wikilink. Aliases: translator-link1, translator1-link.
  • OR: for multiple translators, use translator-link1 through translator-linkn. Aliases: translator1-link through translatorn-link.
• collaboration: Name of a group of authors or collaborators; requires author, last, or vauthors listing one or more primary authors; follows author name-list; appends "et al." to author name-list.
• others: To record other contributors to the work, including illustrators. For the parameter value, write Illustrated by John Smith.
• Note: When using shortened footnotes or parenthetical referencing styles with templates, do not use multiple names in one field, or else the anchor will not match the inline link.

Editors

• editor-last: surname of editor. Do not wikilink—use editor-link instead. Where the surname is usually written first—as in Chinese—or for corporate authors, simply use editor-last to include the same format as the source. Aliases: editor-last1, editor1-last, editor-surname, editor-surname1, editor1-surname, editor, editor1.
  • editor: This parameter is used to hold the complete name of a single editor (first and last), or the name of an editorial committee. This parameter should never hold the names of more than one editor. Supports accept-this-as-written markup.
  • editor-first: given or first names of editor, including title(s); example: Firstname Middlename or Firstname M. or Dr. Firstname M., Sr. Do not wikilink—use editor-link instead. Aliases: editor-first1, editor1-first, editor-given, editor-given1, editor1-given.
  • OR: for multiple editors, use editor-last1, editor-first1 through editor-lastn, editor-firstn (Aliases: editorn-last, editor-surnamen or editorn-surname; editorn-first, editor-givenn or editorn-given; editorn). For an individual editor plus an institutional editor, you can use |editor-first1=... |editor-last1=... |editor2=....
  • editor-link: title of existing Wikipedia article about the editor—not the editor's website; do not wikilink. Aliases: editor-link1.
  • OR: for multiple editors, use editor-link1 through editor-linkn (alias editorn-link).
  • name-list-style: accepts a limited list of keywords as value; when set to amp, ampersand, or &, inserts an ampersand between the last two names in a name list; when set to and, inserts the conjunction 'and' between the last two names of a name list; when set to vancdisplays name lists in Vancouver style when the lists use the last/first forms of name parameters.
• veditors: comma separated list of editor names in Vancouver style; enclose corporate or institutional names in doubled parentheses. End with etal if appropriate:
  |veditors=Smythe JB, ((Megabux Corp.)), etal
  • editor-link_n_ and editor-mask_n_ may be used for the individual names in |veditors=, as described above
• Display:
  Use display-editors to control the length of the displayed editor name list and to specify when "et al." is included.
  If authors: Authors are first, followed by the included work, then "In" and the editors, then the main work.
  If no authors: Editors appear before the included work; a single editor is followed by "ed."; multiple editors are followed by "eds."

Title

(See also Help:Citation Style 1 § Titles and chapters.)

• title: Title of source. Can be wikilinked to an existing Wikipedia article or url may be used to add an external link, but not both. If work (or its alias) is defined, then title is displayed in quotes; otherwise, title displays in italics. If script-title is defined, use title to hold a Romanization (if available) of the title in script-title.
  • script-title: Original title for languages that do not use a Latin-based script (Arabic, Chinese, Cyrillic, Greek, Hebrew, Japanese, Korean, etc.); not italicized, follows italicized Romanization defined in title (if present). Must be prefixed with one of the supported language codes to help browsers properly display the script:
    ... |title=Tōkyō tawā |script-title=ja:東京タワー |trans-title=Tokyo Tower ...
  • trans-title: English translation of the title if the source cited is in a foreign language. Displays in square brackets after title. Use of the language parameter is recommended.

Titles containing certain characters will not display and link correctly unless those characters are encoded.

• title-link: Title of existing Wikipedia article about the source named in title – do not use a web address; do not wikilink.

• chapter: The chapter heading of the source. May be wikilinked or may use chapter-url, but not both. Displays in quotes. If script-chapter is defined, use chapter to hold a Romanization (if available) of the title in script-chapter

  • script-chapter: Chapter heading for languages that do not use a Latin-based script (Arabic, Chinese, Cyrillic, Greek, Hebrew, Japanese, Korean, etc); follows Romanization defined in chapter (if present). Must be prefixed with one of the supported language codes to help browsers properly display the script:
    ... |chapter=Tōkyō tawā |script-chapter=ja:東京タワー |trans-chapter=Tokyo Tower ...
  • trans-chapter: English translation of the chapter heading, if the source cited is in a foreign language. Displays in square brackets after the chapter field; if chapter-url is defined, then trans-chapter is included in the link. Use of the language parameter is recommended.

• contribution: A separately-authored part of author's book. May be wikilinked or may use contribution-url, but not both. Values of Afterword, Foreword, Introduction, or Preface will display unquoted; any other value will display in quotation marks. The author of the contribution is given in contributor.

• type: Provides additional information about the media type of the source. May alternatively be used to identify the type of manuscript linked to in the title, if this is not the final version of a manuscript (e.g. if a preprint of a manuscript is freely available, but the version of record is behind a paywall). Format in sentence case. Displays in parentheses following the title. The reserved keyword none can be used to disable the display of a type. Examples: Thesis, Booklet, Accepted manuscript, CD liner, Press release. Alias: medium.

• language: The language (or a comma-separated list of the languages) in which the source is written, as either the ISO 639 language code (preferred) or the full language name. Examples: |language=ru; |lang=fr, pt-br; |lang=Russian; |language=French, Portuguese. See the list of supported codes and names. Do not use templates or wikilinks. Displays in parentheses with "in" before the language name or names. When the only source language is English, no language is displayed in the citation. The use of languages recognized by the citation module adds the page to the appropriate subcategory of Category:CS1 foreign language sources. Because cs1|2 templates are often copied from en.wiki to other wikis, the use of language codes is preferred so that language names render in the correct language and form, e.g. espagnol at a French-language wiki instead of the English word "Spanish". Aliases: lang

Date

"Wikipedia:Undated" redirects here. For undated signatures, see Template:Undated.

• date: Date of referenced source. Can be full date (day, month, and year) or partial date (month and year, season and year, or year). Use same format as other publication dates in the citations.[date 1] Do not wikilink. Displays after the authors and is enclosed in parentheses. If there is no author, then displays after the website and publisher. For acceptable date formats, see Help:Citation Style 1 § Dates.

Shortened footnotes target full citations using the year specified in this parameter. A lowercase letter may be suffixed to the year to disambiguate {{[sfn](/wiki/Template:Sfn "Template:Sfn")}} links to multiple works by the same author in the same year,[more] unless the date is formatted as YYYY-MM-DD. In the latter case, year or ref is required to disambiguate the link targets.

For approximate year, precede with "c. ", like this: |date=c. 1900.

For no date, or "undated", use |date=n.d.

The date of a Web page, PDF, etc. with no visible date can sometimes be established by searching the page source or document code for a created or updated date; a comment for editors such as date=2021-12-25<!--date from page source-->|orig-date=Original date 2011-01-01 can be added.

Automatic date formatting: Citation Style 1 and 2 templates, including this template, automatically render dates in all date parameters (such as |date=, |publication-date=, |access-date=, |archive-date=, etc.) except for |orig-date= in the style specified by the article's {{[use dmy dates](/wiki/Template:Use%5Fdmy%5Fdates "Template:Use dmy dates")}} or {{[use mdy dates](/wiki/Template:Use%5Fmdy%5Fdates "Template:Use mdy dates")}} template. See those templates' documentation for details.

• year: Year of publication. The more flexible |date= parameter also handles a year by itself. Do not use in combination with the |date= parameter, unless both of the following conditions are met:
  1. Shortened footnotes target multiple citations with same last name and year of publication. (This situation necessitates a [CITEREF](/wiki/Wikipedia:Citation%5Ftemplates%5Fand%5Freference%5Fanchors "Wikipedia:Citation templates and reference anchors") disambiguator, usually a lowercase letter suffixed to the year.)
  2. The |date= format is YYYY-MM-DD. (This format prevents the addition of a disambiguating letter to the year.)
• orig-date: Original publication date or year; displays in square brackets after the date (or year). For clarity, please supply specifics. For example: |orig-date=First published 1859 or |orig-date=Composed 1904. As |orig-date= does not support automatic date formatting, use the same date format as defined by |df= (or, if it exists in the article, by |cs1-dates= of a {{[use dmy dates](/wiki/Template:Use%5Fdmy%5Fdates "Template:Use dmy dates")}} or {{[use mdy dates](/wiki/Template:Use%5Fmdy%5Fdates "Template:Use mdy dates")}} template), or as used in the |date= parameter. Alias: orig-year
• df: date format; sets rendered dates to the specified format; does not support date ranges or seasonal dates; overrides the automatic date formatting described above. Accepts one value which may be one of these:
  dmy – set publication dates to day month year format; access- and archive-dates are not modified;
  mdy – as above for month day, year format
  ymd – as above for year initial numeric format YYYY-MM-DD
  dmy-all – set publication, access-, and archive-dates to day month year format;
  mdy-all – as above for month day, year format
  ymd-all – as above for year initial numeric format YYYY-MM-DD

1. ^ Publication dates in references within an article should all have the same format. This may be a different format from that used for archive and access dates. See MOS:DATEUNIFY.

Work

• work (required by {{[cite journal](/wiki/Template:Cite%5Fjournal "Template:Cite journal")}} and {{[cite magazine](/wiki/Template:Cite%5Fmagazine "Template:Cite magazine")}}): Name of the work containing the source; may be wikilinked if relevant. Displays in italics. If the name of the periodical changed over time use the name at the time of the source's publication. If script-work is defined, use work to hold a Romanization (if available) of the title in script-work. Aliases: journal, newspaper, magazine, periodical, website. Use Latin script. For languages written in non-Latin based scripts (Arabic, Chinese, Cyrillic, Greek, Hebrew, Indic, Japanese, Korean, etc.) use a standard Romanization in this field.
  • script-work: Work title in its original, non-Latin script; not italicized, follows italicized Romanization defined in work (if present). Must be prefixed with one of the supported language codes to help browsers properly display the script. Leave empty for Latin-based scripts (Czech, French, Turkish, Vietnamese, etc.). Aliases: script-journal, script-newspaper, script-magazine, script-periodical, script-website.
  • trans-work: English translation of the work title if the source cited is in a foreign language. Displays in square brackets after work or script-work. Aliases: trans-journal, trans-newspaper, trans-magazine, trans-periodical, trans-website.
    ... |work=Zhōngguó piàofáng |script-work=zh:中国票房 |trans-work=China Box Office ...
  • issue: When the publication is one of a series that is published periodically. Alias: number. When the issue has a special title of its own, this may be given, in italics, along with the issue number, e.g. |issue=2, ''Modern Canadian Literature''. Please choose either |issue= or |number= depending on what is used in the actual publication. If a publication carries both issue and number designations (typically one being a year-relative and the other an absolute value), provide them both, for example |issue=2 #143. Displayed in parentheses following volume.

When set, work changes the formatting of other parameters in the same citation:

title is not italicized and is enclosed in quotes.

chapter does not display (and will produce an error message).

Publisher

• publisher: Name of publisher; may be wikilinked[1] if relevant. The publisher is the company, organization or other legal entity that publishes the work being cited. For self-published works (i.e., where the publisher is the same as the author or creator) state |publisher=self-published.[2] Do not use the publisher parameter for the name of a work (e.g. a website, book, encyclopedia, newspaper, magazine, journal, etc.). If the name of the publisher changed over time, use the name as stated in the publication or used at the time of the source's publication. Corporate designations such as "Ltd", "Inc.", or "GmbH" are not usually included. This parameter is most commonly used for books, and rarely for websites or periodicals (although it may be used instead of work in some cases). Omit where the publisher's name is substantially the same as the name of the work (for example, The New York Times Co. publishes The New York Times newspaper, so there is no reason to name the publisher). Displays after title.
• place: For news stories with a dateline, the location where the story was written. If the name of the location changed over time, use the name as stated in the publication or used at the time of the source's publication. In earlier versions of the template this was the publication place, and for compatibility, will be treated as the publication place if the publication-place parameter is absent; see that parameter for further information. Alias: location
• publication-place: Geographical place of publication; generally not wikilinked; omit when the name of the work includes the publication place, for example, The Boston Globe, The Times of India. Displays after the title. If the name of the publication place changed over time, use the name as stated in the publication or used at the time of the source's publication. If only one of publication-place, place, or location is defined, it will be treated as the publication place and will show after the title; if publication-place and place or location are defined, then place or location is shown before the title prefixed with "written at" and publication-place is shown after the title.
• publication-date: Date of publication when different from the date the work was written. If date (or year) is also defined and is different, then publication-date displays preceded by "published" and enclosed in parentheses, following publisher. If date (or year) is not defined, publication-date is displayed as date. Use the same format as other dates in the article; do not wikilink.
• via: Name of the content deliverer (if different from publisher). via is not a replacement for publisher, but provides additional detail. It may be used when the article is attributed to a different publication (e.g. in Yahoo News) but cannot be traced, when the content deliverer (e.g. NewsBank) presents the source in a format different from the original, when the URL provided does not make clear the identity of the deliverer, where no URL or DOI is available (e.g. EBSCO_host_), or if the deliverer requests attribution. See the access level parameters to display access restrictions, and the agency parameters if the original source is a news agency or wire service.

Edition, series, volume

• edition: When the publication has more than one edition; for example: "2nd", "Revised", and so forth. Appends the string " ed." after the field, so |edition=2nd produces "2nd ed." Does not display if a periodical field is defined.
• series or version: When the source is part of a series, such as a book series or a journal, where the issue numbering has restarted.
• volume: For one publication published in several volumes. Displays after the title and series fields; volume numbers should be entered just as a numeral (e.g. 37). Volume values that are wholly digits, wholly uppercase Roman numerals, or fewer than five characters will appear in bold. Any alphanumeric value of five or more characters will not appear in bold. In rare cases, publications carry both an ongoing volume and a year-related value; if so, provide them both, for example |volume=IV / #10.

In-source locations

• page: The number of a single page in the source that supports the content. Use either |page= or |pages=, but not both. Displays preceded by p. unless |no-pp=yes. If hyphenated, use {{hyphen}} to indicate this is intentional (e.g. |page=3{{hyphen}}12), otherwise several editors and semi-automated tools will assume this was a misuse of the parameter to indicate a page range and will convert |page=3-12 to |pages=3{{ndash}}12. Alias: p.
• OR: pages: A range of pages in the source that supports the content. Use either |page= or |pages=, but not both. Separate using an en dash (–); separate non-sequential pages with a comma (,); do not use to indicate the total number of pages in the source. Displays preceded by pp. unless |no-pp=yes.
  Hyphens are automatically converted to en dashes; if hyphens are appropriate because individual page numbers contain hyphens, for example: pp. 3-1–3-15, use double parentheses to tell the template to display the value of |pages= without processing it, and use {{hyphen}} to indicate to editors that a hyphen is really intended: |pages=((3{{hyphen}}1{{ndash}}3{{hyphen}}15)). Alternatively, use |at=, like this: |at=pp. 3-1–3-15. Alias: pp.
  • no-pp: Set to yes, y, or true to suppress the p. or pp. notations where this is inappropriate; for example, where |page=Front cover or |pages=[passim](/wiki/Passim "Passim").
• OR: at: For sources where a page number is inappropriate or insufficient. Overridden by |page= or |pages=. Use only one of |page=, |pages=, or |at=.
  Examples: page (p.) or pages (pp.); section (sec.), column (col.), paragraph (para.); track; hours, minutes and seconds; act, scene, canto, book, part, folio, stanza, back cover, liner notes, indicia, colophon, dust jacket, verse.
• For |quote-page= and |quote-pages= used in conjunction with |quote=, see here.

URL

• url: URL of an online location where the text of the publication named by title can be found. Cannot be used if title is wikilinked. If applicable, the link may point to the specific page(s) referenced. Remove tracking parameters from URLs, e.g. #ixzz2rBr3aO94 or ?utm_source=google&utm_medium=...&utm_term=...&utm_campaign=.... For linking to pages in PDF files or in Google Books, see WP:PAGELINKS. Do not link to any commercial booksellers, such as Amazon; use |isbn= or |oclc= to provide neutral search links for books. Invalid URLs, including those containing spaces, will result in an error message.
  • access-date: Full date when the content pointed to by url was last verified to support the text in the article; do not wikilink; requires url; use the same format as other access and archive dates in the citations.[date 1] Not required for linked documents that do not change. For example, access-date is required for online sources, such as personal websites, that do not have a publication date; see WP:CITEWEB. Access dates are not required for links to published research papers or published books. Note that access-date is the date that the URL was found to be working and to support the text being cited. See "Automatic date formatting" above for details about interaction with {{[use dmy dates](/wiki/Template:Use%5Fdmy%5Fdates "Template:Use dmy dates")}} and {{[use mdy dates](/wiki/Template:Use%5Fmdy%5Fdates "Template:Use mdy dates")}}. Can be hidden or styled by registered editors. Alias: accessdate.
  • archive-url: The URL of an archived snapshot of a web page. Typically used to refer to services such as Internet Archive (see Help:Using the Wayback Machine); requires archive-date and url. By default (overridden by |url-status=live) the archived link is displayed first, with the original link at the end. Alias: archiveurl.
    * archive-date: Archive service snapshot date; preceded in display by default text "archived from the original on". Use the same format as other access and archive dates in the citations. This does not necessarily have to be the same format that was used for citing publication dates.[date 1] Do not wikilink; templated dates are discouraged. See "Automatic date formatting" above for details about interaction with {{[use dmy dates](/wiki/Template:Use%5Fdmy%5Fdates "Template:Use dmy dates")}} and {{[use mdy dates](/wiki/Template:Use%5Fmdy%5Fdates "Template:Use mdy dates")}}. Alias: archivedate.
    * url-status: A control parameter to select one of |url= or |archive-url= to link |title=; requires url and archive-url. Use {{[dead link](/wiki/Template:Dead%5Flink "Template:Dead link")}} to mark dead |url= when there is no |archive-url=.
    Accepts multiple keywords:
    * dead – (default condition when |url-status= omitted or empty) selects |archive-url=
    * live – selects |url=; used when |url= is preemptively archived with |archive-url=
    * deviated – selects |archive-url=; used when |url= is still live but no longer supports the text in a Wikipedia article
    * unfit – selects |archive-url=; used when |url= links to vice (gambling, pornography), advertising, malware, phishing, compromised, other malicious, or other unsuitable page; links to |url= are suppressed in the rendering. If an entire domain is unsuitable, consider instead usurpation or blacklist. Bot help is available at WP:URLREQ
    * usurped – selects |archive-url=; used when the domain in |url= no longer serves its original intent, particularly when the domain has been (mis)appropriated by other entities such as vice, reseller, malware, phishing, compromised, other malicious, and advertising sites; links to |url= are suppressed in the rendering. Bot help is available at WP:URLREQ
    * bot: unknown – Editors may encounter this value which is left behind by a bot that has visited the reference and wasn't able to determine the status of the url. The page will be automatically placed in Category:CS1 maint: bot: original URL status unknown when this value is present, and per the instructions in that category, editors manually evaluate the state of the URL and change the parameter value appropriately.
    * archive-format: File format of the work referred to by archive-url; for example: DOC or XLS; displayed in parentheses after the archive link. HTML is implied and should not be specified. PDF is auto-detected and should not be specified. Does not change the external link icon (except for PDF). Note: External link icons do not include alt text; thus, they do not add file format information for the visually impaired. (This is not a concern with PDF, because the auto-detection will add "(PDF)" as descriptive text.) See Using |format=
  • url-access: See Access indicators discussion
• format: File format of the work referred to by url; for example: DOC or XLS; displayed in parentheses after title. (For media format, use type.) HTML is implied and should not be specified. PDF is auto-detected and should not be specified. Does not change the external link icon (except for PDF). Note: External link icons do not include alt text; thus, they do not add file format information for the visually impaired. (This is not a concern with PDF, because the auto-detection will add "(PDF)" as descriptive text.) See Using |format=

URLs must begin with a supported URI scheme. http:// and https:// will be supported by all browsers; however, ftp://, gopher://, irc://, ircs://, mailto: and news: may require a plug-in or an external application and should normally be avoided. IPv6 host-names are currently not supported.

If URLs in citation template parameters contain certain characters, then they will not display and link correctly. Those characters need to be percent-encoded. For example, a space must be replaced by %20. To encode the URL, replace the following characters with:

Single apostrophes do not need to be encoded; however, unencoded multiples will be parsed as italic or bold markup. Single curly closing braces also do not need to be encoded; however, an unencoded pair will be parsed as the double closing braces for the template transclusion.

1. ^ a b Access-date and archive-date in references should all have the same format – either the format used for publication dates, or YYYY-MM-DD. See MOS:DATEUNIFY.

Chapter URL

• chapter-url: URL of an online location where the text of the publication named by chapter or contribution can be found. Cannot be used if those parameters are wikilinked. Should be at the same site as url, if any. If chapter-url is used, url should only be used if the beginning of the work and the cited chapter are on separate webpages at the site. Aliases: contribution-url, section-url.
• chapter-format: Format of the work referred to by chapter-url; for example: PDF, DOC, or XLS; displayed in parentheses after chapter. HTML is implied and should not be specified. Does not change the external link icon. Note: External link icons do not include alt text; thus, they do not add format information for the visually impaired.

Anchor

Not to be confused with § Identifiers.

Further information: § Anchored citations

• ref: the citation's HTML anchor identifier, when different from its default. When set, |ref=ID generates an anchor with the given ID (the id= attribute in the citation's <cite id="ID"> HTML tag). Setting |ref=ID identifies the template as a target and allows wikilinking to full references, especially useful with short-form citations like shortened notes and parenthetical referencing. The default anchor ID is suitable for use with {{sfn}} and {{harv}} templates. Since April 2020, the parameter / keyword pair |ref=harv has no special meaning; this deprecated setting should not be used and may be removed from existing cs1|2 templates. To inhibit anchor ID creation, set |ref=none. Aliases: none.

Identifiers

Not to be confused with § Anchor.

• id: A unique identifier, used where none of the specialized identifiers are applicable; wikilink or use an external link template as applicable. For example, |id=NCJ 122967 will append "NCJ 122967" at the end of the citation. You can use templates such as |id={{NCJ|122967}} to append NCJ 122967 instead.

The following identifiers create links and are designed to accept a single value. Using multiple values or other text will break the link and/or invalidate the identifier. In general, the parameters should include only the variable part of the identifier, e.g. |rfc=822 or |pmc=345678.

• arxiv: arXiv identifier; for example: |arxiv=hep-th/9205027 (before April 2007) or |arxiv=0706.0001 (April 2007 – December 2014) or |arxiv=1501.00001 (since January 2015). Do not include extraneous file extensions like ".pdf" or ".html". Aliases: eprint.
• asin: Amazon Standard Identification Number; if first character of asin value is a digit, use isbn. Because this link favours one specific distributor, include it only if standard identifiers are not available. Example |asin=B00005N5PF. Aliases: ASIN.
  • asin-tld: ASIN top-level domain for Amazon sites other than the US; valid values: ae, au, br, ca, cn, de, es, fr, in, it, jp, mx, nl, pl, sa, se, sg, tr, uk. Aliases: none.
• bibcode: bibcode; used by a number of astronomical data systems; for example: 1974AJ.....79..819H. Aliases: none.
• biorxiv: bioRxiv id, as in the entire DOI (e.g. 10.1101/078733 for http://biorxiv.org/content/early/2016/10/01/078733 or https://doi.org/10.1101/078733; 10.1101/2020.07.24.220400 for https://doi.org/10.1101/2020.07.24.220400). Aliases: none.
• citeseerx: CiteSeerX id, a string of digits and dots found in a CiteSeerX URL (e.g. 10.1.1.176.341 for https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.176.341). Aliases: none.
• doi: Digital object identifier; for example: 10.1038/news070508-7. It is checked to ensure it begins with (10.). Aliases: DOI.
  • Supports accept-this-as-written markup to indicate valid DOIs using a non-standard format, see below.
  • doi-broken-date: Date a valid DOI was found to be non-working/inactive at https://doi.org. Use the same format as other dates in the article. Aliases: none.
• eissn: International Standard Serial Number for the electronic media of a serial publication; eight characters may be split into two groups of four using a hyphen, but not an en dash or a space; example |eissn=1557-2986. Aliases: EISSN.
  • Supports accept-this-as-written markup to indicate valid eISSNs using a non-standard format, see below.
• hdl: Handle System identifier for digital objects and other resources on the Internet; example |hdl=20.1000/100. Aliases: HDL.
• isbn: International Standard Book Number; for example: 978-0-8126-9593-9. (See Wikipedia:ISBN and ISBN § Overview.) Hyphens in the ISBN are optional, but preferred. Use the ISBN actually printed on or in the book. Use the 13-digit ISBN – beginning with 978 or 979 – when it is available. If only a 10-digit ISBN is printed on or in the book, use it. ISBNs can be found on the page with the publisher's information – usually the back of the title page – or beneath the barcode as a number beginning with 978 or 979 (barcodes beginning with any other numbers are not ISBNs). For sources with the older 9-digit SBN system, use sbn. Do not convert a 10-digit ISBN to 13-digit by just adding the 978 prefix; the last digit is a calculated check digit and just making changes to the numbers will make the ISBN invalid. This parameter should hold only the ISBN without any additional characters. It is checked for length, invalid characters – anything other than numbers, spaces, and hyphens, with "X" permitted as the last character in a 10-digit ISBN – and the proper check digit. Aliases: ISBN.
  • Use the {{Format ISBN}} template within the parameter – in the form |isbn={{Format ISBN|9780812695939}} – if you are unsure of how any particular ISBN should be hyphenated, as the pattern varies by country and publisher.
  • Supports accept-this-as-written markup to indicate valid ISBNs using a non-standard format, see below.
• ismn: International Standard Music Number; for example: 979-0-9016791-7-7. Hyphens or spaces in the ISMN are optional. Use the ISMN actually printed on or in the work. This parameter should hold only the ISMN without any additional characters. It is checked for length, invalid characters – anything other than numbers, spaces, and hyphens – and the proper check digit. Aliases: ISMN.
• issn: International Standard Serial Number; eight characters may be split into two groups of four using a hyphen, but not an en dash or a space; example |issn=2049-3630. Aliases: ISSN.
  • Supports accept-this-as-written markup to indicate valid ISSNs using a non-standard format, see below.
• jfm: Jahrbuch über die Fortschritte der Mathematik; do not include "JFM" in the value; example |jfm=53.0144.01. Aliases: JFM.
• jstor: JSTOR reference number; for example: |jstor=3793107. Aliases: JSTOR.
• lccn: Library of Congress Control Number. When present, alphabetic prefix characters are to be lower case and without a space; example |lccn=79-57364 or |lccn=2004042477 or |lccn=e09001178. Aliases: LCCN.
• mr: Mathematical Reviews; example |mr=630583. Aliases: MR.
• oclc: OCLC Number for looking up publications in the WorldCat union catalog; example |oclc=9355469. Aliases: OCLC.
• ol: Open Library identifier; do not include "OL" in the value; example |ol=7030731M. Aliases: OL.
• osti: Office of Scientific and Technical Information; example |osti=4367507. Aliases: OSTI.
• pmc: PubMed Central; use article number for open repository full-text of a journal article, e.g. |pmc=345678. Do not include "PMC" in the value. See also the pmid parameter, below; these are two different identifiers. Aliases: PMC.
  • pmc-embargo-date: Date that pmc goes live; if this date is in the future, then pmc is not linked until that date. Aliases: none.
• pmid: PubMed; use unique identifier; example |pmid=17322060 See also the pmc parameter, above; these are two different identifiers. Aliases: PMID.
• rfc: Request for Comments; example |rfc=3143. Aliases: RFC.
• sbn: Standard Book Number; example |sbn=356-02201-3. Aliases: SBN.
  • Supports accept-this-as-written markup to indicate valid SBNs using a non-standard format, see below.
• ssrn: Social Science Research Network; example |ssrn=1900856. Aliases: SSRN.
• s2cid: Semantic Scholar corpus ID; example |s2cid=37220927. Aliases: S2CID.
• zbl: Zentralblatt MATH; example |zbl=0472.53010 For zbMATH search results like JFM 35.0387.02 use |jfm=35.0387.02. Aliases: ZBL.

In very rare cases, identifiers are published which do not follow their defined standard format or use non-conforming checksums. These would typically cause an error message to be shown. Do not alter them to match a different checksum. In order to suppress the error message, some identifiers (|doi=, |eissn=, |isbn=, |issn=, and |sbn=) support a special accept-this-as-written markup which can be applied to disable the error-checking (as |<param>=((<value>))). If the problem is down to a mere typographical error in a third-party source, correct the identifier value instead of overriding the error message.

For some identifiers, it is possible to specify the access status using the corresponding |<param>-access= parameter.

For {{cite journal}}, some identifiers (specifying free resources) will automatically be linked to the title when |url= and |title-link= are not used to specify a different link target. This behaviour can be overridden by one out of a number of special keywords for |title-link= to manually select a specific source (|title-link=pmc or |title-link=doi) for auto-linking or to disable the feature (|title-link=none).

It is not necessary to specify a URL to a link identical to a link also produced by an identifier. The |url= parameter (or |title-link=) can then be used for providing a direct deep link to the corresponding document or a convenience link to a resource that would not otherwise be obviously accessible.

Quote

• quote: Relevant text quoted from the source. Displays enclosed in quotes. If script-quote is defined, use quote to hold a Romanization (if available) of the text in script-quote. When quoting a copyrighted text, only brief quotations to attribute a point of view or idea are permitted; extensive quotations are prohibited.
  • script-quote: Original quotation for languages that do not use a Latin-based script (Arabic, Chinese, Cyrillic, Greek, Hebrew, Japanese, Korean, etc.); not italicized, follows italicized Romanization defined in quote (if available). Alias: none. Must be prefixed with one of the supported language codes to help browsers properly display the script:
    ... |quote=Tōkyō tawā |script-quote=ja:東京タワー |trans-quote=Tokyo Tower ...
  • trans-quote: English translation of the quotation if the source quoted is in a foreign language. Displays in square brackets. Alias: none.
• quote-page: The number of a single page quoted in |quote=. Use either |quote-page= or |quote-pages=, but not both. Should be a subset of the page(s) specified in |page=, |pages= or |at=. Displays preceded by p. unless |no-pp=yes. If hyphenated, use {{hyphen}} to indicate this is intentional (e.g. |quote-page=3{{hyphen}}12). Alias: none.
• OR: quote-pages: A list or range of pages quoted in |quote=. Use either |quote-page= or |quote-pages=, but not both. Should be a subset of the pages specified in |pages= or |at=. Separate using an en dash (–); separate non-sequential pages with a comma (,). Displays preceded by pp. unless |no-pp=yes is defined. Hyphens are automatically converted to en dashes; if hyphens are appropriate because individual page numbers contain hyphens, for example: pp. 3-1–3-15, use double parentheses to tell the template to display the value of |quote-pages= without processing it, and use {{hyphen}} to indicate to editors that a hyphen is really intended: |quote-pages=((3{{hyphen}}1{{ndash}}3{{hyphen}}15)). Alias: none.

Display options

• mode: Sets element separator, default terminal punctuation, and certain capitalization according to the value provided. For |mode=cs1, element separator and terminal punctuation is a period (.); where appropriate, initial letters of certain words are capitalized ('Retrieved...'). For |mode=cs2, element separator is a comma (,); terminal punctuation is omitted; where appropriate, initial letters of certain words are not capitalized ('retrieved...'). These styles correspond to Citation Style 1 and Citation Style 2 respectively. To override default terminal punctuation use postscript.
• author-mask:
• contributor-mask:
• editor-mask:
• interviewer-mask:
• subject-mask:
• translator-mask:
  Replaces the name of the (first) author with em dashes or text. Set <name>-mask to a numeric value n to set the dash n em spaces wide; set <name>-mask to a text value to display the text without a trailing author separator; for example, "with". The numeric value 0 is a special case to be used in conjunction with <name>-link—in this case, the value of <name>-link will be used as (linked) text. In either case, you must still include the values for all names for metadata purposes. Primarily intended for use with bibliographies or bibliography styles where multiple works by a single author are listed sequentially such as shortened footnotes. Do not use in a list generated by {{[reflist](/wiki/Template:Reflist "Template:Reflist")}}, <references /> or similar as there is no control of the order in which references are displayed. Mask parameters can take an enumerator in the name of the parameter (e.g. |authorn-mask=) to apply the mask to a specific name.
• display-authors:
• display-contributors:
• display-editors:
• display-interviewers:
• display-subjects:
• display-translators:
  Controls the number of author (or other kind of contributor) names that are displayed. By default, all authors are displayed. To change the displayed number of names, set the parameter to the desired number. For example, |display-authors=2 will display only the first two authors in a citation (and not affect the display of the other kinds of contributors). |display-authors=0 is a special case suppressing the display of all authors including the et al. |display-authors=etal displays all authors in the list followed by et al. Aliases: none.
• postscript: Controls the closing punctuation for a citation; defaults to none. Additional text, or templates that render more than a single terminating punctuation character, will generate a maintenance message. |postscript= is ignored if quote is defined.

Subscription or registration required

• WP:URLACCESSWP:URLACCESS

Citations of online sources that require registration or a subscription are acceptable in Wikipedia as documented in Verifiability § Access to sources. As a courtesy to readers and other editors, editors should signal restrictions on access to material provided via the external links included in a citation. These levels describe requirements or constraints related to accessing and viewing the cited material; they are not intended to indicate the ability to reuse, or the copyright status, of the material, since that status is not relevant to verifying claims in articles.

Four access levels can be used:

• access indicator for named identifiers:
  • free: the source is free to read for anyone
• access indicators for url-holding parameters:

As there are often multiple external links with different access levels in the same citation, each value is attributed to a specific external link.

Access indicators for url-holding parameters

Online sources linked by |url=, |article-url=, |chapter-url=, |contribution-url=, |entry-url=, |map-url=, and |section-url= are presumed to be free-to-read. When they are not free-to-read, editors should mark those sources with the matching access-indicator parameter so that an appropriate icon is included in the rendered citation. Because the sources linked by these URL-holding parameters are presumed to be free-to-read, they are not marked as free. If the registration/limited/subscription access to the source goes dead and is no longer available, then remove the access-indicator parameter and add |archive-url= and |archive-date= values if possible.

URL-holding and access-indicator parameters

URL	Access	Allowed keywords
|url=	|url-access=	registration limited subscription
|article-url=	|article-url-access=
|chapter-url=	|chapter-url-access=
|contribution-url=	|contribution-url-access=
|entry-url=	|entry-url-access=
|map-url=	|map-url-access=
|section-url=	|section-url-access=

For example, this cites a web page that requires registration but not subscription:

{{cite web |url=https://example.com/nifty_data.php |url-access=registration |date=2021-04-15 |title=Nifty example data}}

which renders as:

"Nifty example data". 2021-04-15.

Access indicator for named identifiers

• WP:DOIACCESSWP:DOIACCESS

Links inserted by named identifiers are presumed to lie behind a paywall or registration barrier – exceptions listed below. When they are free-to-read, editors should mark those sources with the matching access-indicator parameter so that an appropriate icon is included in the rendered citation. When the sources linked by these named-identifier parameters are not presumed to carry a free-to-read full text (for instance because they're just abstracting services), they may not be marked as limited, registration, or subscription.

Named-identifier and access-indicator parameters

Identifier	Access	Allowed keywords
|bibcode=	|bibcode-access=	free
|doi=	|doi-access=
|hdl=	|hdl-access=
|jstor=	|jstor-access=
|ol=	|ol-access=
|osti=	|osti-access=
|ssrn=	|ssrn-access=
|s2cid=	|s2cid-access=

Some named-identifiers are always free-to-read. For those named identifiers there are no access-indicator parameters; the access level is automatically indicated by the template. These named identifiers are:

• |arxiv=
• |biorxiv=
• |citeseerx=
• |medrxiv=
• |pmc=
• |rfc=

For an embargoed pmc that will become available in the future, see pmc-embargo-date.

Tracking of free DOIs

• The template is able to recognize known free-to-read DOI registrants, based on a list in Module:Citation/CS1/Configuration. Once a free registrant is identified, the 10.xxxx/... part of the DOI associated with the registrant can be added to the list under local function build_free_doi_registrants_table(). If |doi-access=free is not set, it will place the page in Category:CS1 maint: unflagged free DOI, which is routinely cleared by User:Citation bot.
• The template is also able to recognize known free-to-read journals, assuming they have a clear 10.xxxx/yyyy.... DOI pattern. Once that pattern is identified, it can be added to Module:Citation/CS1/Configuration under local extended_registrants_t = { with the format ['XXXX'] = {'YYYY'},. If there are multiple journals with the same DOI prefix, they can be grouped together with the format ['XXXX'] = {'YYYY', 'ZZZZ', '...'},.
• If you add a free registrant/free journal to the lists in Module:Citation/CS1/Configuration, leave a note at User talk:Citation bot so the bot knows about it.

Examples

Books

Web

Journals, newspapers, magazines, or other periodicals

Conference papers and public lectures

Parts of books, including encyclopedia articles

Republications, or edited quotations in a periodical article

Press release

Anchored citations

Not to be confused with § Identifiers.

This template can generate a citation that can be combined with shortened footnotes or parenthetical referencing. It does this by creating an HTML anchor containing an ID. The special parameter |ref= generates an anchor ID suitable for Harvard referencing templates such as {{harv}} as specified in the next section; an anchor ID is generated by default.

To disable anchor generation, specify |ref=none. You can also specify the ID directly, using the |ref=ID parameter. For example, suppose an article's References section contains the markup:

• {{Citation |author=Sigmund Freud |title=Civilization and Its Discontents |date=1930 |ref=CivDis}}

which generates the citation:

• Sigmund Freud (1930), Civilization and Its Discontents

Then, the markup "([[#CivDis|Freud 1930]])" generates a parenthetical reference "(Freud 1930)" containing a wikilink to the citation (try clicking on the wikilink).

Anchors for Harvard referencing templates

IDs compatible with Harvard referencing templates such as {{harv}} are computed from the last names of the authors (or editors, if no authors are given) and the year of the cited source. For example, the markup "{{harv|Wright|Evans|1851|p=ix}}" generates the Harvard reference "(Wright & Evans 1851, p. ix)", which wikilinks to the citation whose markup and appearance are shown below:

• {{Citation |last1=Wright |first1=Thomas |last2=Evans |first2=R. H. |title=Historical and Descriptive Account of the Caricatures of James Gillray |location=London |publisher=Henry G. Bohn |date=1851 |oclc=59510372}}
• Wright, Thomas; Evans, R. H. (1851), Historical and Descriptive Account of the Caricatures of James Gillray, London: Henry G. Bohn, OCLC 59510372

In this example the {{citation}} template defines, and the {{harv}} template uses, the HTML ID "CITEREFWrightEvans1851", composed by concatenating the string "CITEREF" with the last names of the authors and the year. The {{harvid}} template can be used to generate such IDs, for example, {{harvid|Wright|Evans|1851}} generates "CITEREFWrightEvans1851".

Related methods which leave only a number in the text are to use the {{harvnb}} template enclosed in the html code, or to use the {{sfn}} template alone. The example above would be <ref>{{harvnb|Wright|Evans|1851|p=ix}}</ref> or {{sfn|Wright|Evans|1851|p=ix}} both of which generate a footnote, such as

17. Wright & Evans 1851, p. ix

The names of only the first four authors are used; other author names are not concatenated to the ID. If no author names are given, editor names are used instead.

Last names are used, as specified by the parameters |last1= (or |last=), |last2=, |last3=, and |last4=, and similarly for |editor1-last= etc. and for |inventor1-last= etc. If a full name is given but no last name is specified, this template falls back on the full name, but this usage is not recommended. For example, in "{{Citation |author=Sigmund Freud |title=The Ego and the Id |date=1923}}" no last name is given, so this citation cannot be combined with the Harvard reference "{{harv|Freud|1923}}". To make these {{citation}} and {{harv}} invocations compatible, either replace "|author=Sigmund Freud" with "|first=Sigmund |last=Freud", or add "|ref={{harvid|Freud|1923}}" to the {{citation}} invocation, or add the same ref parameter (say, "|ref=EgoId") to both the {{citation}} and the {{harv}} invocations.

Similarly, the year is used, as specified by |year=. If no year is given, this template attempts to derive the year from |date= (or, if no date is given, from |publication-date=) by applying the MediaWiki § Time function. This heuristic works with most common date formats (American, International and ISO 8601 standard format YYYY-MM-DD as listed in WP:MOS), but may not work as expected with other formats, so when in doubt it may be safer to use |year=.

IDs must be unique

Names, years, and hand-specified IDs must be chosen so that the IDs are unique within a page; otherwise the HTML will not conform to the W3C standards, and any references to the citations will not work reliably. For example, suppose a page contains the following two citations with {{harv}}-compatible IDs:

• Montes, G.; Halterman, J. S. (2008a), "Association of Childhood Autism Spectrum Disorders and Loss of Family Income", Pediatrics, 121 (4): e821–e826, doi:10.1542/peds.2007-1594, PMID 18381511
• Montes, G.; Halterman, J. S. (2008b), "Child Care Problems and Employment Among Families with Preschool-aged Children with Autism in the United States", Pediatrics, 122 (1): e202–e208, doi:10.1542/peds.2007-3037, PMID 18595965

If these citations were altered to say "2008" rather than "2008a" and "2008b", the resulting page would not work, because the two different citations would both attempt to use the ID "CITEREFMontesHalterman2008". To avoid this problem, distinguish the citations by appending suffixes to the years, e.g. "|date=2008a" and "|date=2008b", as was done above. Any Harvard references to these citations should use years with the same suffixes.

It is good practice to verify that a page does not contain duplicate IDs by using the W3C Markup Validation Service; see External links.

Dates

1. ^ The format of dates in the references of an article should use consistent and unambiguous styles. Example formats used in Wikipedia citations include:
   • 2009
   • 2009-09-14 (ISO 8601 standard format: YYYY-MM-DD)
   • 14 September 2009
   • September 14, 2009 (with comma)
   • September 2009
     Dates should not be linked (say, to a Wikipedia article of the same name) in references. Please see Wikipedia:Manual of Style (dates and numbers) § Dates for more guidance about formatting dates.

See Wikipedia:Citing sources § Citation templates and tools for a list of tools that can help create a reference in the "citation" format.

TemplateData

Template:Citation uses standard parameter set; TemplateData has errors:

• |people= is not a valid parameter

The Citation template generates a citation for a book, periodical, contribution in a collective work, or a web page. It determines the citation type by examining which parameters are used.

Template parameters[Edit template data]This template has custom formatting.

This template produces COinS metadata; see COinS in Wikipedia for background information.

See also

• Wikipedia:Citation templates
• Wikipedia:Inline citation
• Wikipedia:Parenthetical referencing
• For a comparison of citations using templates with citations written freehand, see Wikipedia:Citing sources/Example edits for different methods § Footnotes

Notes

1. ^ The pipe trick does not work inside references, so be sure to insert a full wikilink.
2. ^ Compare archived talk page.