แม่แบบ:Harvard citation documentation

is designed to be used to create lc=y, a citation style where there is an author-date citation in a footnote and a complete citation in a references section at the end of the article. (See example below.) This citation style is used to reduce clutter in the edit window and to combine identical citations.
Common problems and known workarounds are given in the section possible issues section below.
There are several other templates that are designed for use with shortened footnotes. They differ slightly in the way they format the author-date citation and how much of their functionality is automated. A full list of these related templates is below.
Note that the use (or even non-use) of these templates is an element of citation "style", and adding or removing them in articles with an established style should be consistent with that style. See WP:CITEVAR. 

**Usage**
generates an "author-date" style short-cite from the following parameters:
with-  – required; surname of first author or corporate author- – – positional parameters; surnames of next three authors-  – required; four-digit year; may have a lowercase disambiguation letter- p – specific page referenced in the source- pp – comma-separated list of individual pages and / or range(s) of pages referenced in the source - loc – in-source location when p and pp are inappropriate; may be used to supplement p and pp; information such as a section or figure number.
Typical usage is shown in the example below. The text and the footnote are connected by a bi-directional link -- clicking on the superscript takes the reader to the footnote, clicking on the footnote number takes them back to the superscript. The clicking on the short citation takes them to the full citation in the references section.

**Parameters**

**Author(s) and year**
The author and the year of publication are the only required parameters. Up to four authors can be given as parameters. 
The possible issues section below describes workarounds for various common problems, such as large number of authors, no author name, multiple works in the same year, multiple authors with same last name and others. 

**Location in the source text**
The optional parameters p, pp and loc can be used to indicate the location in the source, such as page numbers. For single pages, use p; for multiple pages (such as ranges), use pp. Use of p for multiple pages or pp for single pages can cause cite errors. loc can be used to specify a location in the source in another way, such as section numbers or chapters. The parameters page and pages exist as aliases for p and pp, respectively.

**Additional text**
The optional parameter postscript or ps can be used to change the text which appears at the end of the note in the reference list. (See § Adding additional comments or quotes and § No closing period, below.) The postscript is only effective the first time sfn is used for a particular author, year and location.

**Hard-coded link names**
Not available in sfn and similar templates.
The optional parameter ref is used to create a unusually named link from the short citation to the full citation. This parameter is usually not necessary, and it is more common to use sfnRef or harvid in the reference section.  If you specify none, no hyperlink is created. However, if one does not want the link, it is always possible to simply use plain text instead of the template. The parameter Ref is an alias for ref.

**Possible issues**

**Adding additional comments or quotes**
The templates harvnb or harvtxt can be used to add quotes or additional comments into the footnote. This effect can also be achieved using sfn by adding a quote or comment to loc. Examples are below.
 In the past, the use of ps has been advised to hold this additional information, but it is not suitable for this purpose. Two or more sfn templates with the same authors, same year, and same page, but different ps will result in a  message.  This message happens because the reference names that sfn creates will be the same, but the content between the o tag and the c tag will be different.  A workaround is to convert one or some of the sfn templates to harvnb wrapped in ref tags.

**Adding a URL for the page or location**
If a specific link to the page or section is available, a URL can be added to the location or page number.

**A citation inside an explanatory footnote**
Sometimes an explanatory footnote requires a citation. Templates like sfn can't be directly imbedded between ref tags, because the following message will be produced: .
The templates efn and notelist can be used to create separate explanatory footnotes from short citations, as shown in the first example. An article that uses this technique extensively is Chinese Room. 
It is also possible to use the magic word  and the sfn template will work correctly inside the footnote, as shown in the second example.

**Multiple lists of inline citations**
Sometimes there is a need to create two or more separate lists of inline footnotes. For example some family trees are contained in templates, they are transluded into several biographies, and they have their own self contained citations (see Template:Houston family tree and the article Margaret Lea Houston).
To facilitate this, while the main page uses the standard 1,2,3 footnote counting, it is common for family trees to use the efn template with a group parameter set—for example efn-lg (lower-greek). The efn templates are text templates, to link some or all of the content of the efn template to a  long citation template such as cite book place harvnb or harv within the efn template. 

**More than one work in a year**
Where there is a need to cite more than one work by the same author published in the same year, the standard way to disambiguate such works is to add a letter suffix after the year element of the sfn template (e.g. 2006a and 2006b). Make sure to add the disambiguation letter to the matching full citation, (e.g. ).

**Templates that use Module:Citation/CS1**
When sfn is used with citation or  templates, a year-suffix letter may be added to date for all accepted date formats except year-initial numeric (YYYY-MM-DD). It is not necessary to include both date and year (see exception below). If both are included, year is used for the CITEREF anchor to be compliant with legacy citations.
2013a: simple year only dates
Jan 2013b or Winter 2013b: month or season and year dates
9 November 2013b or November 9, 2013b: full dates
June–July 2013c or Winter–Spring 2013c: month or season ranges and year dates
c. 2013d: circa year dates
 or : year ranges
n.d.e: no date (n.d.)
NB_YEAR2013x-11-09: not supported, the template must use 2013x. If month and day should be part of the citation as well, both parameters need to be given: 2013-11-09 2013x. In this case, date is used for citation display and metadata purposes, and year for link disambiguation.

**More than one author with the same last name**
The above solution to add a letter suffix after the year element also works for multiple authors with the same last name. For example, both Richard Bushman and Claudia Lauper Bushman published books in 2006. To differentiate between the two books, the first one can be given the year "2006a" and the second one "2006b".

**Large number of authors**
Only the first four authors are required by the template. Listing more is not supported. It is also possible to use the  in the citation template, which allows a more concise citation in the article text.

**No author name in citation template**
Some sources do not have a single author with a last name, such as a magazine article or a report from a government institution. There is no consensus (in Wikipedia or among citation styles) about how to format author–date citations for works that do not have a specific author. Several choices are:
# For a newspaper or periodical, you may use the name of the paper and the date.
# For a publication by an institution, use either:
## The initials of the institution
## The name of the institution
# Alternatively, some style guides recommend using the title of the article.
# Other style guides recommend using "Anonymous" or "Anon."
An article should adopt one of these styles consistently. Using  in the citation template can handle these cases.

**Citation has |date= and no |year**
Either the date or year of a citation template can be matched—the template logic can extract the year from a full date. If the date parameter is not a full date, then the extraction will fail. If the link does not seem to work, it also possible to set both date and year parameters. The template will display the date and use the year for the anchor. These two examples show a year being successfully extracted from full date.

**Using  with**
The  family of templates use parameter harvid to create an anchor for the Harvard citation templates. This must be set to a concatenation of the parameters passed to the Harvard citation template.

**Citation format does not support anchors:**
In a few very rare cases, it may be impossible for the citation templates to create an anchor. Either (1) the citation is formatted with a template that does not support the ref parameter or (2) the source can't be described using our citation templates at all. In these cases, it is possible to use wikicite to make the anchor. (As of November 2010, there are only approximately 100 articles that require this technique.) It is also possible that (3) local editors would prefer not to use citation templates. In this case, it is important to discuss what the local editors would like to do about the bad links. It is always possible to simply remove harv or sfn, leaving plain text without links.
It is also possible to use o to achieve the same effect, but this may not be compatible with HTML 5.

**Citation has multiple authors and no date**
The templates assume that the last unnamed parameter is the year. Where there are multiple authors and no year, the template will form a correct link but will display the last author as if it were a year.  To force the displayed text to show all authors as names, the following workaround may be used:

**No closing period: |ps=none**
Using none in sfn removes the final period. Compare the two examples. Suppressing the default period (full stop) ensures consistency with Citation style 2, as produced by Citation, which does not use a trailing period (full stop) when rendering full citations. The postscript is only effective the first time sfn is used for a particular author, year, and location.  will also suppress terminal punctuation. Follow-on editors who encounter 'empty' parameters can't know if a previous editor intended to leave that parameter blank. Using the keyword none is a positive indication of the previous editor's intent.

**Wikilink to citation does not work**
If an article is using this template, and nothing happens when you click on the highlighted wikilink from a Harvard style citation to a full citation at the bottom of the page, there are several possible solutions. If:
# The correct citation does not appear at the bottom of the article. Solution: Find the source (it may be copied from an article on a similar subject), and check that it verifies the text. If the source can't be found, tag the citation with citation not found.
# The correct citation appears at the bottom of the article, and
## The Harvard citation uses a template (such as sfn or harv):
### The citation uses a template from the list at Citation Style 1:
#### The name is spelled or capitalized differently here than in the citation. Solution: check the source for the correct spelling, and use the same spelling, spacing, and capitalization in both the short and full citations.
#### The year is different here than the citation. Solution: check the source for the correct year, and use the same year in both the short and full citations.
#### The template has a date field and no year field, but the format of the date field is unusual. Solution: Try to fix the date. If the link still does not work, add year to the citation template. (It's okay if it has both.)
#### The citation does not have an author's, or an editor's, last name (authors take precedence over editors). Solution: check that  is set correctly (see below).
### The citation uses a Citation Style Vancouver template. Solution: check that harvid is set correctly (see below).
### The citation uses a template that does not support ref (See Wikipedia:Citation templates and reference anchors). Solution: Consider modifying the template to support ref. Alternatively, an anchor can be created using .
### The full citation does not use a template:
#### It has no wikicode to create an anchor. Solution: If  citation templates are used liberally throughout the article, then reformat the full citation with the appropriate  template (and set the ref appropriately, if necessary). Otherwise consult with local editors on the talk page about how to proceed. Either add  templates and harv templates, or remove all templates, depending on what local editors prefer. A few articles use wikicite to create an anchor as an alternative to standard templates.
#### It uses a cite span to create an anchor. Solution: remove the cite span (these are deprecated) and proceed following the  recommendation immediately above.
#### It uses wikicite. Solution: Check that the text in  matches the text in wikicite.
## If the Harvard citation uses a handwritten wikilink, such as :
### The citation uses a citation template which supports ref (See Wikipedia:Citation templates and reference anchors). Solution: Check that ref is set to a matching id.
### Otherwise, check that the reference has idcitation with a matching id.
Templates that have broken wikilinks using these templates are added to the category All articles with broken links to citations.

**Link works but displays a no target error**
When a short-cite template links to a full citation that is rendered by a template that wraps a CS1 template, like cite DNB (which wraps cite encyclopedia), a no target error may be displayed even when the short-cite template is valid and the link works. That is a "false positive" error. The error message can be suppressed by adding yes to the template.

**Other author–date citation templates**
There are several templates used to create short citations; they differ in the use and placement of parentheses, in the separator before the page or location, and in whether a terminal full stop (period) is present:
Full citations can be created manually or by templates:-  templates- citation
All of these templates have the same parameters and basic functionality. This page describes all of them except the parameters of sfnm and harvs; please see their documentation pages. Editors editing one of these templates are requested to make parallel changes to the other versions.

**Applications of these templates**

**Harvard citation:**
Template harv creates a parenthetical reference with a link to the full citation in the references section at the bottom of the article.

**Shortened footnote:  or**
Template harvnb inside a o span can be used to create a shortened footnote that is linked to the full citation at the bottom of the article. Template sfn (without the use of o) has the same effect, automatically adds a period (full stop) after the page number, and combines identical footnotes automatically.

**In text attribution:**
Template harvtxt can be used to link an in-text attribution to the full citation at the bottom of the page.

**Bundled citation:  or**
Template harvnb can be used to bundle citations. sfnm also produces bundled citations.
Note that sfn is inappropriate for bundled citations; use harvnb or sfnm.

**More exotic Harvard citations:  or**
More exotic Harvard citations can be constructed using the harvs template, such as multiple papers by the same author, using both the first and last names, links to articles about the author, and others. Any kind of unusual link can also be constructed using the idiom parameterslink name. (citeref is a wrapper for harvid making it easier to consistently create such internal links in small superscriptn or plain-text label styles.)
Some articles use this idiom id | link name . See notes on implementation details below.

**Variations**

**Using colon format: harvcol, harvcolnb, harvcoltxt**
Templates harvcol, harvcolnb, and harvcoltxt use a colon to indicate the page number(s) or location.

**Parentheses around the year:  and **
Template sfnp puts parentheses around the year. Compare the two examples.
Similarly, in order to mimic  citations, template harvp puts parentheses around the year.

**Implementation notes**
These templates use two elements: a wikilink in the body of the article, and an anchor in the reference section of the article. Clicking on the wikilink repositions the page at the anchor.

**Citation template anchor**
The most common citation templates are  or . By default, Module:Citation/CS1 creates an anchor params=name="CITEREF" followed by the concatenation of the following parameters:- last or last1 or surname or surname1 or author-last or author-last1 or author1-last or author-surname or author-surname1 or author1-surname or author or author1 or authors,- last2 or surname2 or author-last2 or author2-last or author-surname2 or author2-surname or author2,- last3 or surname3 or author-last3 or author3-last or author-surname3 or author3-surname or author3,- last4 or surname4 or author-last4 or author4-last or author-surname4 or author4-surname or author4,- editor-last or editor-last1 or editor1-last or editor-surname or editor-surname1 or editor1-surname or editor1 or editor,- editor-last2 or editor2-last or editor-surname2 or editor2-surname or editor2,- editor-last3 or editor3-last or editor-surname3 or editor3-surname or editor3,- editor-last4 or editor4-last or editor-surname4 or editor4-surname or editor4,- date, year
This covers the most common templates. Information about all of the templates is available at Wikipedia:Citation templates and reference anchors.
Use of the date parameter in place of the year parameter in citation templates is preferred.

**Harvard citation wikilink**
The Harvard citation templates create a wikilink to the anchor. For example 4=p=25 produces the link #CITEREFSmith2006 and 5=title=My Life produces the anchor CITEREFSmith2006.

**Using CITEREF directly**
A few articles create a custom ID using CITEREF, either in place of the Harvard citation template (e.g. ) or as a value for ref in the citation template.
Examples:
Where cite_name is a name such as the publisher.
To avoid the sometimes difficult to remember syntax for links to CITEREF anchors, citeref can be used to create internal wikilinks with either small superscript-style labels (like thisn) or plain free-text labels to such anchors. It can be used inside of other citations.
Note that the CITEREF prefix is necessary for the reference tooltips gadget (MediaWiki:Gadget-ReferenceTooltips.js) to detect that a link goes to a citation.

**'s ref name**
Template sfn creates a named footnote, so that identical footnotes are combined automatically. The footnote name begins with FOOTNOTE followed by a concatenation of the arguments to sfn. E.g.: this template call 4=p=26 should have exactly the same functionality as  which, in turn, has the same functionality as content=.
The ref name becomes more complicated when the page (p) parameter includes a URL, e.g. , which, once defined, can be called by tag|ref|empty|params=name="FOOTNOTEJoyce1903httpsarchiveorgdetailsaconcisehistory00joycgoogpagen226 213". The "p=" and the characters |,:,.,/,?,=; are therefore stripped out of the URL.
The call to harvnb has been subst'ed for quicker load times.

**Tracking categories==