Help:Footnotes

For the official guideline on citing sources, see Wikipedia:Citing sources.

This page explains how to create footnotes on Wikipedia pages. Footnotes are used most commonly to provide references (bibliographic citations) to reliable sources in articles, although they have other uses as well. They are generated using the following tags in the editable text of a page: <ref>...</ref> within the text, and <references /> or {{Reflist}} at the end where the footnote list is to appear.

The most common use of footnotes in Wikipedia articles is to provide inline citations to reliable sources, although footnotes can also be used for other purposes. The use of <ref> tags is not required by any policy or guideline, and other systems of inline citation, including parenthetical referencing, may be used at the editors' discretion. However, <ref> tags are by far the most popular system for inline citations.

This page concerns technical methods for creating footnotes. Only certain types of material on the English Wikipedia are required to have an inline citation to a reliable source. There is no requirement to provide a citation for every sentence, because multiple sentences may be supported by the same footnote. For advice on which material should be cited, see WP:MINREF (minimum requirements for all articles), the Wikipedia:Good article criteria (for Good articles), and Wikipedia:When to cite (for Featured articles). For advice on how to organize and format bibliographic citations to reliable sources, see Citing sources and Citation template examples.

Overview

File:WP-Footnotes illustration.jpg

How a footnote is created in the editable text of a page. (Click to see more detail.)

The footnoting system involves two elements:

• Footnote markers. These are links, usually in the form Template:Dummy refTemplate:Dummy ref, etc. Clicking on a footnote marker will take you to the correspondingly numbered footnote.
• The footnotes themselves. These appear in a list (usually placed near the end of the article), and include links back to the corresponding footnote markers.

Footnote markers are generated using <ref> tags. The list of footnotes is generated using the <references /> tag, or the corresponding {{Reflist}} template, placed in the editable text at the point where the footnotes are to appear. The text of a footnote is placed between opening <ref> and closing </ref> tags, either at the point where the footnote marker is to appear, or within the <references /> element. If the page contains footnote markers but no footnote list, a red cite error message will appear.

Creating a footnote marker

At the point in the page text where the footnote marker is to appear, enter the text of the footnote and put the two pieces of coding before and after the footnote-text, like this:

<ref>LibreOffice For Starters, First Edition, Flexible Minds, Manchester, 2002, p. 18</ref>

This will create a footnote marker (automatically numbered). The footnote text itself will appear in the footnote list, generated as described below. If there is no footnote list markup, a red warning message will appear, reminding you to write the markup that generates the list.

You can include formatting and links in a footnote in the usual way, although certain features, such as the pipe trick and template substitution, will not work in footnotes. For the formatting of references, citation templates, such as a generic {{citation}}, or more specific {{cite book}}, {{cite web}}, etc., are available, although many editors prefer not to use them. See Citing sources for details on how references can be structured.

If a footnote contains a link to an external site, and the link contains some non-displaying characters, it may not display correctly. In particular, a line break (carriage return) embedded in the descriptive text will affect display. This may happen if the description is pasted from a source with line breaks, and is particularly difficult to find if the hard break is inserted where it happens to be at the end of a line on the edit screen. Example: this footnote is formatted correctly. This is formatted identically (with different wording), but has an embedded line break after "page.". These footnotes display as:

To aid readability in the edit window, a single newline can be added after the closing </ref> tag before continuing with the text of the paragraph. This has the same effect as putting a space after the closing tag.

Multiple references to the same footnote

It is possible to refer to the same footnote more than once, in other words to generate several footnote markers, all with the same number, which link to the same footnote. To achieve this, named footnotes (named references) are used. The same naming system is also used for list-defined references.

A footnote is named using the <syntaxhighlight lang="text" enclose="none">name</syntaxhighlight> attribute of the <ref> tag. Choose a name (such as "Perry"), and then at one of the footnote marker points (it makes sense to choose the first), enter the footnote like this:

<ref name="Perry">Perry's Handbook, Sixth Edition, McGraw-Hill Co., 1984</ref>

Then you can create another identical marker linking to the same footnote from any other point in the text, by entering the following (note the final slash):

<ref name="Perry" />

Names for footnotes and groups must follow these rules:

• Names are case-sensitive
• Names may not be purely numeric
• Quotes are optional if the only characters used are letters A–Z, a–z, digits 0–9 and the symbols !$%&()*,-.:;<@[]^_`{|}~
• Inclusion of any other characters including spaces requires that the name be enclosed in straight quotes (")
• Quote-enclosed names may not include a less-than sign (<) or a quote symbol (")

• Please consider keeping names simple and restricted to the standard English alphabet and numerals.
• You may optionally provide names even when the name is not required.

Note that when Shortened footnotes are employed (using {{sfn}} to create footnotes under {{Reflist}} and {{efn}} to create explanatory notes under {{Notelist}}) then naming is not required because identical footnote markers are automatically identified and consolidated into a single footnote.

Creating the footnote list

At the point where you want the text of the footnotes to appear, usually at the end of the article in a section titled "References" or "Notes (see the Footers in the layout guideline for more information), put the following markup:

<references />

A commonly used alternative, which includes some formatting, is the {{Reflist}} template:

{{Reflist}}

This template has parameters available for splitting the list into columns, and for controlling their width. For example, {{Reflist|2}} puts the list of footnotes into two columns. (For more options, see the reflist template documentation.)

The footnote list must be inserted on the page below (after) all the footnote markers.

If the page has markup to generate a footnote list, but there are no footnote markers on the page, the list will simply appear as a blank line. No warning or error message is displayed.

List-defined references

Main page: Help:List-defined references

In order to make the article text easier to read in the edit window, particularly in sections with many citations, editors may decide to write all footnotes in the shorter "named" form. This can be done using the list-defined references function, where the content of the references is defined within the reference list, rather than in the article text. The syntax is as follows:

Markup	Renders as
The quick brown fox jumps over the lazy dog.<ref name="LazyDog" /> <references> <ref name="LazyDog">This is the lazy dog reference.</ref> </references>	The quick brown fox jumps over the lazy dog.

This can also be done using the {{Reflist}} template with a |refs= parameter:

Markup	Renders as
The quick brown fox jumps over the lazy dog.<ref name="LazyDog" /> Amazingly few discotheques provide jukeboxes.<ref name="Jukeboxes" /> How razorback-jumping frogs can level six piqued gymnasts.<ref name="JumpingFrogs" /> ==References== {{Reflist| refs= <ref name="LazyDog">This is the lazy dog reference.</ref> <ref name="Jukeboxes">This is the jukeboxes reference.</ref> <ref name="JumpingFrogs">This is the jumping frogs reference.</ref> }}	The quick brown fox jumps over the lazy dog. Amazingly few discothèques provide jukeboxes. How razorback-jumping frogs can level six piqued gymnasts. References

The references will appear numbered in the order that they are referred to in the text, regardless of how they are ordered within the reflist/references template. References which are list-defined but unused (that is, are not in the text) will show a cite error message.

If it becomes necessary to convert references from the list-defined to the inline format or vice versa, the page Converting between references formats documents procedures for doing so.

What it looks like

When a page with footnotes is displayed in a browser, the <ref> tags in the main text are converted to auto-numbered superscripts, like this:

Clicking on a numbered superscript takes you straight to the text of the corresponding footnote. (The ^{[citation needed]} item is not a footnote marker; it is produced by the {{fact}} template, used to indicate a point where a reference ought to be provided.)

The <references /> tag or {{Reflist}} template is expanded to show the text of the footnotes against their corresponding numbers, like this:

For single-reference footnotes, clicking on the caret Template:Dummy backlink takes you back to the footnote marker in the main text. For multiple-reference footnotes, the links back to the main text are distinguished by letter superscripts Template:Dummy backlink. Clicking on a letter superscript takes you to the corresponding marker in the main text.

Previewing edits

When you edit a single section of a page, the footnotes list will not be visible when you preview your edits. Thus you ordinarily cannot see how your footnotes will later appear when you save your edits.

You can insert a {{Reflist}} into the edited section temporarily and remove it before saving; you will still not be able to see named references which were defined in other sections.

Tools that can be used are the User:Anomie/ajaxpreview.js script or the wikEd gadget.

Grouping footnotes

See also: Template:efn

Sometimes it is useful to group the footnotes into separate lists, for example to separate explanatory notes from references, or to list references for tables, image captions, infoboxes and navboxes. This can be accomplished with the group attribute. The sequence of footnote labels is independent in each group.

Editor-defined groups

Footnotes that do not use the group attribute have plain automatic numbers for their labels. When the group attibute is used, in-text footnote labels are formed from the group name, a space and the automatic number. However the labels in the footnote list entries just use the numbers without the prefix.

Markup	Renders as
This part of the text requires clarification,<ref group="note">Listed separately from the citation</ref> whereas the entire text is cited.<ref>Citation.</ref> ==Notes== {{Reflist|group=note}} ==References== {{Reflist}}	This part of the text requires clarification, whereas the entire text is cited. Notes References

Predefined groups

For technical details, see Help:Cite link labels.

There are several predefined group names that apply a style to the footnote labels and to the reference list:

Label styles

Group name	Style	Sample
	Decimal numbers (default)	1 2 3 4 5 6 7 8 9 10
decimal	Decimal numbers	1 2 3 4 5 6 7 8 9 10
lower-alpha	Alpha, lower case	a b c d e f g h i j
upper-alpha	Alpha, upper case	A B C D E F G H I J
lower-greek	Greek, lower case	α β γ δ ε ζ η θ ι κ
lower-roman	Roman, lower case	i ii iii iv v vi vii viii ix x
upper-roman	Roman, upper case	I II III IV V VI VII VIII IX X

The in-text footnote is defined using one of the group names, for example:

<ref group=lower-alpha>Footnote 1</ref>

The reference list is invoked using {{Reflist}} with the group name. The group name must not be enclosed by quotes. For example:

Markup	Renders as
Lorem ipsum dolor sit amet.<ref group=lower-alpha>Footnote 1</ref> Cconsectetur adipisicing elit.<ref group=lower-alpha name=footnote2>Footnote 2</ref>. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.<ref group=lower-alpha name=footnote2 /> {{Reflist|group=lower-alpha}}	Lorem ipsum dolor sit amet. Cconsectetur adipisicing elit. Sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.

Issues

• Backlink labels are always styled as lower-alpha. This can be confusing when the footnotes are also labelled alphabetically.
• The entries in the reference list will show the default decimal styling if:
  • The value for |group= does not exactly match one of the predefined values.
  • The value for |group= is enclosed by quotes.
  • {{Reflist}} is indented with the <syntaxhighlight lang="text" enclose="none">:</syntaxhighlight> markup.
  • <references /> is used instead of {{Reflist}}
• The entries in the reference list will have no styling if:
  • A reference is included in {{navbox}} or one of the variants and the style is set to bodyclass=hlist; to resolve this, replace the style with listclass=hlist.

Multiple reference lists

It is possible to include multiple instances of the reference list markup <references /> or {{Reflist}} on a page. Care must be taken to ensure that multiple reference lists are closed so that the references intended for one list do not appear in another list. To close the reference list markup, simply use any parameter in the reference list markup. Normally different reference lists would use different groups, so the reference list markup will be closed.

In this example, the reference list markup is unclosed and the reference list is repeated in the two subsequent lists and the third in-text footnote number is rendered incorrectly:

Markup	Renders as
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. <ref>Reference 1</ref> {{Reflist}} Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.<ref>Reference 2</ref> {{Reflist}} Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.<ref>Reference 3</ref> {{Reflist}}	Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

To prevent this and close references so that they are not rendered incorrectly, the reference list markup must include any parameter, such as |group=, |refs= or a column parameter. If parameters are not desired, a dummy parameter may be used, by convention |close=. For example:

Markup	Renders as
Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. <ref>Reference 1</ref> {{Reflist|close}} Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.<ref>Reference 2</ref> {{Reflist|close}} Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.<ref>Reference 3</ref> {{Reflist|close}}	Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur.

Embedding references within footnotes

Explanatory notes may need to be referenced. Due to limitations in the Cite.php software, reference tags cannot be nested—a set of <ref>...</ref> tags cannot be placed inside another pair of <ref>...</ref> tags; attempting to do so will result in a cite error.

The magic word <syntaxhighlight lang="text" enclose="none">#tag:ref</syntaxhighlight> may be used to nest references. The markup is:

{{#tag:ref|refcontent|name=name|group=groupname}}

Where refcontent may include <ref>...</ref> tags. The name and groupname are optional, but must come after refcontent. If the groupname is not specified, then the main and nested references will be rendered into the same reference list. Attempting to use #tag:ref more than once within list-defined references will result in a cite error.

Example:

Markup	Renders as
The quick brown fox jumps over the lazy dog.{{#tag:ref|A footnote.<ref>A reference for the footnote.</ref>|group="nb"}} ==Notes== {{Reflist|group="nb"}} ==References== {{Reflist}}	The quick brown fox jumps over the lazy dog. Notes References

The syntax of #tag:ref is not obvious, as parameters must come after the content; {{refn}} may be used in place of the <syntaxhighlight lang="text" enclose="none">#tag:ref</syntaxhighlight> markup.

Markup	Renders as
The quick brown fox jumps over the lazy dog.{{refn|group="nb"|A footnote.<ref>A reference for the footnote.</ref>}} ==Notes== {{Reflist|group="nb"}} ==References== {{Reflist}}	The quick brown fox jumps over the lazy dog. Notes References

Similarly, {{efn}} can simplify the usage of {{refn}}.

Explanatory notes

See also: Wikipedia:Citing sources#Variation in citation methods and Wikipedia:Manual of Style/Layout#Notes and References

For Shortened footnotes with explanatory footnotes, see Help:Shortened footnotes#Explanatory notes.

Most footnotes are citations, which identify sources. Another kind of footnote is an explanatory footnote which is a comment that would be too detailed or too awkward to include in the body of the article. The Wikipedia Manual of style does not mandate a layout for explanatory footnotes at the bottom of the article, and in fact provides for several approaches that are acceptable. An important factor whether or not Shortened footnotes are used or not. Here are some common approaches to laying out the footnotes.

A

This example uses standard footnotes with all citations and explanatory notes in a single Notes sections:

Markup	Renders as
The Sun is pretty big.<ref>Miller, ''The Sun'', Oxford, 2005, p. 23. But Miller points out that the Sun is not as large as some other stars.</ref> But the Moon<ref>The Moon goes by other names, such as Selena - see, for example Brown, ''The Moon'', 2006, Penguin, p 623.</ref> is not so big.<ref>Brown, ''The Moon'', 2006, Penguin, p. 46. Historically the Moon was not always considered to be large. For a discussion, see Miller, ''The Sun'', Oxford, 2005, p 411.</ref> The Sun is also quite hot.<ref>Smith, ''The Universe'', Random House, 2005, p. 334.</ref> ==Notes== {{Reflist}}	The Sun is pretty big. But the Moon is not so big. The Sun is also quite hot. Notes

B

This example uses Shortened footnotes with a References section and combines explanatory notes and citations in a Notes section:

Markup	Renders as
The Sun is pretty big.<ref>Miller, p. 23. But Miller points out that the Sun is not as large as some other stars.</ref> But the Moon<ref>The Moon goes by other names, such as Selena - see, for example Brown, p 623.</ref> is not so big.<ref>Brown, p. 46. Historically the Moon was not always considered to be large. For a discussion, see Miller, p 411.</ref> The Sun is also quite hot.<ref>Smith, p. 334.</ref> ==Notes== {{Reflist}} ==References== * Brown, ''The Moon'', Penguin. 2001. * Miller, ''The Sun'', Oxford, 2005. * Smith, ''The Universe'', Random House, 2005.	The Sun is pretty big. But the Moon is not so big. The Sun is also quite hot. Notes References Brown, The Moon, Penguin. 2001. Miller, The Sun, Oxford, 2005. Smith, The Universe, Random House, 2005.

C

This example uses list-defined references mixed with explanatory notes.

Markup	Renders as
The Sun is pretty big.<ref name=Foot01/> But the Moon<ref name=Foot02/> is not so big.<ref name=Foot03/> The Sun is also quite hot.<ref name=Foot04/> ==Notes== {{reflist|refs= <ref name=Foot01>Miller, ''The Sun'', Oxford, 2005, p. 23. But Miller points out that the Sun is not as large as some other stars.</ref> <ref name=Foot02>The Moon goes by other names, such as Selena - see, for example Jones, ''The Solar System'', MacMillan, 2005, p 623.</ref> <ref name=Foot03>Brown, ''The Moon'', 2006, Penguin, p. 46. Historically the Moon was not always considered to be large, see, for example Peterson, ''Astronomy'', MacMillan, 2005, p 623.</ref> <ref name=Foot04>Smith, ''The Universe'', Random House, 2005, p. 334.</ref> }}	The Sun is pretty big. But the Moon is not so big. The Sun is also quite hot. Notes

D

This example uses list-defined references and creates a separate notes section by using group names.

Markup	Renders as
The Sun is pretty big.<ref name=Foot01/><ref group=Note name=Note01/> But the Moon<ref group=Note name=Note02/> is not so big.<ref name=Foot02/><ref group=Note name=Note03/> The Sun is also quite hot.<ref name=Foot03/> ==Notes== {{reflist|group=Note|refs= <ref name=Note01>But Miller points out that the Sun is not as large as some other stars.</ref> <ref name=Note02>The Moon goes by other names, such as Selena.</ref> <ref name=Note03>Historically the Moon was not always considered to be large.</ref> }} ==References== {{reflist|refs= <ref name=Foot01>Miller, ''The Sun'', Oxford, 2005, p. 23.</ref> <ref name=Foot02>Brown, ''The Moon'', 2006, Penguin, p. 46.</ref> <ref name=Foot03>Smith, ''The Universe'', Random House, 2005, p. 334.</ref> }}	The Sun is pretty big. But the Moon is not so big. The Sun is also quite hot. Notes References

E

This example is similar as the previous one above, except that it allows references embedded within footnotes.

Markup	Renders as
The Sun is pretty big.<ref name=Miller2005/>{{efn|But the Sun is not as large as some other stars.<ref name=Miller2005/>}} But the Moon{{efn|The Moon goes by other names, such as Selena.<ref name=Jones2005/>}} is not so big.<ref name=Brown2006/>{{efn|Historically the Moon was not always considered to be large.<ref name=Peterson2005/>}} The Sun is also quite hot.<ref name=Smith2005/> ==Notes== {{notelist}} ==References== {{reflist|refs= <ref name=Miller2005>Miller, ''The Sun'', Oxford, 2005, p. 23.</ref> <ref name=Jones2005>Jones, ''The Solar System'', MacMillan, 2005, p 623.</ref> <ref name=Peterson2005>Peterson, ''Astronomy'', MacMillan, 2005, p 623.</ref> <ref name=Brown2006>Brown, ''The Moon'', 2006, Penguin, p. 46.</ref> <ref name=Smith2005>Smith, ''The Universe'', Random House, 2005, p. 334.</ref> }}	The Sun is pretty big. But the Moon is not so big. The Sun is also quite hot. Notes References

Citing one book repeatedly with different page numbers

Main page: Help:References and page numbers

Suppose you would like to cite one book, but different facts appear on different pages. You would like to cite the book again and again, but point each fact to the proper page. Suppose one fact is on page 8, a different fact on page 12, a third fact on page 18, a fourth fact on page 241. You could put a line in the "pages" parameter saying "see pages 8, 12, 18, 241" but a fact-checker might have to check all of them before figuring out the right one. Or, you could duplicate the entire citation for the book in each instance, but that would be redundant. One common approach is to use shortened citations, which requires the use of a References section following the footnotes section. Another approach is to attach a {{rp|8}} right after the reference pointer. and replace the "8" with whatever page number.

For example:

Markup	Renders as
Schudson said the Constitution shaped citizenship in fundamental ways.<ref name="Schudson">{{Cite book | last = Schudson | first = Michael | title = The Good Citizen: A Brief History of American Civic Life | publisher = Simon & Schuster | date = 1998 | url = http://books.google.com/books?id=aawMAQAAMAAJ | isbn =0-684-82729-8 }}</ref>{{rp|8}} But elections in early American politics did not generate much interest<ref name="Schudson"/>{{rp|12}} while "open discussion of differences" was generally avoided.<ref name="Schudson"/>{{rp|18}} Citizenship later shifted to a polity of essentially "self-absorbed citizens", according to his analysis.<ref name="Schudson"/>{{rp|241}}	Schudson said the Constitution shaped citizenship in fundamental ways. But elections in early American politics did not generate much interest while "open discussion of differences" was generally avoided. Citizenship later shifted to a polity of essentially "self-absorbed citizens", according to his analysis. References

When using list-defined references, {{r}} can be used for the same style of in-text page references.

Limitations

• Templates can't be substituted within <ref>...</ref> tags. {{subst:foo}} will remain as-is.
• <ref> tags can't be nested. See #Embedding references within footnotes above for solution.

See also

• Template:Harvard citation#Using CITEREF directly and {{sfnref}}
• Wikipedia:Citing sources/Further considerations — a how-to article with some additional considerations for citing sources
• Wikipedia:Help desk — to ask questions about using footnotes in articles if you weren't able to find the information you need on this help page.

Ways to get help

70px Find where to ask questions or make comments If you place {{helpme}} on your talk page, a helper will visit you there as soon as possible! Join the #wikipedia-en-help IRC channel for real-time chat. New to IRC? Click here to be connected instantly! Find and directly contact an actively editing user at Highly Active Users.

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