Wikipedia:Manual of Style/Footnotes

As of late December 2005, the Cite.php extension to MediaWiki has been installed on all Wikimedia wikis adding built-in support for footnotes. This page describes how to use this system to add footnotes to an article.

Footnotes are an excellent way to cite sources, but they are not the only way; some articles use inline links instead. Also, Cite.php footnotes are not the only way to make footnotes. Many articles use templates to create footnotes, particularly if they use Harvard references. For a general overview, see Wikipedia:Citing sources.

Before Cite.php footnotes were available, the same functionality was achieved with a system called Wikipedia:Footnote3 that used templates. Converting old Footnote3 notes to MediaWiki footnotes can make the references in an article easier to maintain.

Footnote overview

A footnote is a note placed at the bottom of a page of a document that comments on, and may cite a reference for, a part of the main text. The connection between the relevant text and its footnote is often indicated with a number or symbol which is used both after the text fragment and before the footnote.

Footnotes are sometimes useful for relevant text that would distract from the main point if embedded in the main text, yet are helpful in explaining a point in greater detail. Footnotes are also often used to cite references which are relevant to a text. Citation of sources is important in supporting Verifiability, a key aspect of Wikipedia.

How to use

The basic concept of the <ref> tag is that it inserts the text enclosed by the ref tags as a footnote in a designated section, which you indicate with the placeholder tag <references/>. The new format cannot be used interchangeably with the old format - you must pick one or the other.

If you forget to include <references/> at the end of the article, none of the footnotes will appear.

This page itself uses footnotes, such as the one at the end of this sentence. If you view the Wikicode of this page by clicking "Edit this page", you can see a working example of footnotes.

Example

According to scientists, the Sun is pretty big.<ref>Miller, E: "The Sun.", page 23. Academic Press, 2005</ref>
The Moon, however, is not so big.<ref>Smith, R: "Size of the Moon", Scientific American, 46(78):46</ref>

==Notes==
<references/>

Multiple uses of the same footnote

To give a footnote a unique identifier, use <ref name="name">. You can then refer to the same footnote again by using a ref tag with the same name. The text inside the second tag doesn't matter, because the text already exists in the first reference. You can either copy the whole footnote, or you can use a terminated empty ref tag that looks like this: <ref name="name"/>.

In the following example, the same source is cited three times.

This is an example of multiple references to the same footnote.<ref name="multiple">Remember that when you refer to the same footnote multiple times, the text from the first reference is used.</ref>

Such references are particularly useful when citing sources, if different statements come from the same source.<ref name="multiple">This text is superfluous, and won't show up anywhere. We may as well just use an empty tag.</ref>

A concise way to make multiple references is to use empty ref tags, which have a slash at the end.<ref name="multiple" />

==Notes==
<references/>

The text above gives the following result in the article (see also Notes section below):

This is an example of multiple references to the same footnote.

Such references are particularly useful when citing sources, when different statements come from the same source.

A concise way to make multiple references is to use empty ref tags, which have a slash at the end.

Style recommendations

• Internal links should still be used as normal, like this: Wikipedia.
• Citations should always follow punctuation, like this.
• Consider using a separate bibliography section if the same book reference is used in multiple footnotes. In this case, just the page number and book name can be given in each note, following Wikipedia:Citing sources.
• There are templates you can insert between the <ref> and </ref> tags to format bibliographic references for you. You can see some instructions on using these templates at Wikipedia:Template messages/Sources of articles#Citations of generic sources. If you find it easier to type the reference in bibliographic style yourself, you are not obligated to use these templates.

Helping editors unfamiliar with this system of footnotes

Instead of simply adding

<references/>

in the references section, it is possible to add the following:

<!--See http://en.wikipedia.org/wiki/Wikipedia:Footnotes for an explanation of how to generate footnotes using the <ref(erences/)> tags-->
<references/>

The same effect can be obtained (that is, including both the commentary text and the <references/> tag) by putting the following in the references section:

{{subst:footnotes}}

(Maintenance aid: list of Wikipedia articles that used this template "non-subst:")

How does it work?

See Meta:Cite/Cite.php for a technical explanation of the template on Meta-Wiki.

Disadvantages and future improvements

• In the old Footnote3 system, links and auto-numbered footnotes pulled from the same counter, which made it difficult to keep the endnotes consistent. With the new Cite.php module, a different issue presents itself: a casual reader might not notice or understand the difference between an external link and an auto-numbered footnote and may be confused, thinking that the numbers aren't in order. For this reason, some editors argue that auto-numbered external links are better not used on the same page with auto-numbered footnotes, which can be avoided, e.g., by making text links for the external references, like this: Kate's Tool, instead of: Kate's Tool[1]. Other editors argue that both citation styles can be used in the same article.
  • Additional references that aren't created with the extension, but added to the References section (as per WP:CITE) do not continue the numbered list.
• Superscripts cause an increase in line spacing for the line they are on in most browsers. Because lines without superscripts are still displayed at the original line spacing, this makes the text unevenly spaced, and this looks bad. This is a general problem with superscripts. It may require CSS changes or even improvements in web browsers or OS font rendering systems (this should be filed as a bug in Bugzilla if it has not already). A fix has been published that eliminates the problem without reducing the size of the superscript. It requires the user to add CSS to their style sheet (monobook.css), and thus works only while logged in.
  • The new style copies the bracketed numbers from the old style, though they are now in superscript. Typical (print) references use plain superscripted numbers with no brackets. If the purpose of the brackets is to increase the clickable area, they could be removed and the same thing done with CSS; increase the horizontal padding around the numbers and vertical arrows instead. Discussion here: w:Wikipedia_talk:Manual_of_Style#Changes_to_Cite. and w:Wikipedia_talk:Footnote3#Superscripts_2.
• Some people like the idea of having sidenotes instead of or in addition to footnotes, especially if this is an option one can turn on and off in Mediawiki preferences. (You can turn a table into a sidenote with style="float: right;".)
• Some people like the idea of "hover" or "tooltip" notes, that appear only when "hovering" over the superscript with the mouse point. (See e.g. Template:Hnote.)
• Bug 2745: Have References text edit window on Edit pages
• The reference content is in the article source code, but displayed in the References section. Some have proposed moving the reference content into the References section to fix these problems:
  • Content from one place rendering in a different place is confusing and unusual.
  • Some references require a lot of markup (citation templates, for instance), which interrupts the article source code, making navigation of the article content more difficult.
  • Editing the format of references requires finding them in the article instead of editing all of them at once in the References section. This is inconvenient and confusing.
  • Section editing is useless if you want to edit references. You can't just edit the References section because that's not where the references actually are. You can't just edit the section that contains the reference since that's not where the rendered references are (so they won't show up in the preview). You have to edit and preview the entire article to see the changes.
  • Since they aren't centralized, it's hard to know if a reference exists already, leading to duplicates which then have to be merged manually.
• Cite.php is not a standard part of MediaWiki, therefore Wikipedia content imported into other MediaWiki installs will by default include ugly, bare <ref> code.
• If a named reference is used in an article, and another reference to the same document is placed before that one, it doesn't work. The reference has to be moved to the first position instead of just using the same name, since the text inside the first reference determines the displayed text. Text inside other references is ignored.

Notes

1. Additional references that aren't created with the extension (as per WP:CITE) do not continue the numbering.

See also

• Wikipedia:Verifiability, which is policy.
• Wikipedia:Citing sources, the relevant style guide.
• Wikipedia:Citing sources/example style, listing also several examples of non-numbered APA style and Harvard referencing techniques
• Wikipedia:Template messages/Sources of articles for complete list of templates that are available for citations; note that several of these templates can easily be combined with "footnote3" footnotes, see Gymnopédie#Notes and References for an example.
• Wikipedia:WikiProject Wikicite: Proposal for use of database of citations.
• Wikipedia:WikiProject Fact and Reference Check
• Other types of numbered footnotes:
  • Wikipedia:Footnote1, a very old, manually-numbered footnote system that should not be used.
  • Wikipedia:Footnote2, another obsolete system that should not be used.
  • Wikipedia:Footnote3, an automatically-numbered footnote system using templates, which is widely used but has been replaced by MediaWiki footnotes.
• meta:Cite.php - description of the <ref>...</ref>/<references/> system at metawiki