The Wikipedia footnotes system uses the Cite.php software extension to generate references. MediaWiki messages are then used to format the display of the inline links and the references.



MediaWiki interface page Use Current
Cite reference link format inline link <sup id="$1" class="reference">[[#$2|&#91;$3&#93;]]</sup>
  1. ref ID: Cite reference link prefix + reference name + numeric starting with 0
  2. backlink ID
  3. count to display
Cite references link many format reference with multiple backlinks <li id="$1"><span class="mw-cite-backlink">^ $2</span> $3</li>
  1. backlink ID
  2. list of links
  3. text of note
Cite references link many and
Cite references link many format [[#$1|<sup>'''''$3'''''</sup>]]
  1. ref ID
  2. numeric value to use as a backlink
  3. custom value to use as a backlink as defined in MediaWiki:Cite references link many format backlink labels
Cite references link many format backlink labels backlink labels used in the reference list currently from a to azz
Cite references link many sep
Cite references link one format reference with single backlink <li id="$1"$4><span class="mw-cite-backlink">'''[[#$2|^]]'''</span> $3</li>
  1. backlink ID - used for creating the number order of the source list.
  2. ref ID - used to link back to the actual reference in the text
  3. text of note - text used above describing the source info
Cite references prefix prefix for <references /> [[:MediaWiki:Cite references prefix]]
Cite references suffix suffix for <references /> [[:MediaWiki:Cite references suffix]]
Cite reference link key with num [[:MediaWiki:Cite reference link key with num]]
  1. key
  2. num
Cite reference link prefix inline link prefix cite_ref-
Cite reference link suffix inline link suffix [[:MediaWiki:Cite reference link suffix]]
Cite references link prefix reference list link prefix cite_note-
Cite references link suffix reference list link suffix [[:MediaWiki:Cite references link suffix]]
Cite references no link [[:MediaWiki:Cite references no link]]
Cite references link many accessibility label accessibility label for screen readers Jump up to:

Classes and CSS[edit]

Class .reference formats the inline link; defined in Common.css

/* Ensure refs in table headers and the like aren't bold or italic */
sup.reference {
    font-weight: normal;
    font-style: normal;

/* Prevent line breaks in silly places:
   3) Ref tags with group names <ref group="Note"> --> "[Note 1]"
sup.reference a {
    white-space: nowrap;

Class .references formats the reference list; defined in Common.css When the inline cite link is clicked, the focus jumps to the proper cite in the reference list. The following rules highlight the cite in light blue. This is supported by Gecko (FireFox) and Webkit (Safari, Chrome) browsers; it is not supported by current versions of Trident, but does work in the Internet Explore 9 platform preview.

/* Highlight clicked reference in blue to help navigation */
div.references li:target,
span.citation:target {
    background-color: #DEF;

Although not specific to references, Common.css does have this line height rule to keep line spacing from breaking on subscript and superscript, as used in the inline link. Internet Explorer 7 has problems with line-height when printing, so it is disabled for IE7 through Common.js.

/* Reduce line-height for <sup> and <sub> */
sup, sub {
    line-height: 1em;

Cite errors are classed with:

<strong class="error mw-ext-cite-error">

The extension uses some modules for CSS:

Reference links[edit]

The inline reference links are defined in MediaWiki:Cite reference link. The default is:

<sup id="$1" class="reference">[[#$2|<nowiki>[</nowiki>$3<nowiki>]</nowiki>]]</sup>


The English Wikipedia customizes this to:

<sup id="$1" class="reference">[[#$2|&#91;$3&#93;]]</sup>

Where the brackets that show enclosing the reference count are enclosed in <span> tags so they can be styled.

Backlink labels[edit]

The backlink label type is defined in MediaWiki:Cite references link many format. This interface page defaults to:



The English Wikipedia interface page is set to:


Changing $2 to $3 changes the backlinks from numeric to alpha. This was modified in 2006 to match the output of ((ref)) which was the predominant method of inserting footnotes at the time.


This is the markup for some simple references

Unnamed <ref>This is an unnamed reference</ref>

Named <ref name="named">This is a named reference</ref>

Named reference used again <ref name="named"/>

Which shows as

Unnamed [1]

Named [2]

Named reference used again [2]

  1. ^ This is an unnamed reference
  2. ^ a b This is a named reference

Which renders as

The MediaWiki messages are combined to form the HTML output

<p>Unnamed <sup id="cite_ref-0" class="reference"><a href="#cite_note-0" title=""><span>[</span>1<span>]</span></a></sup></p>
<p>Named <sup id="cite_ref-named_1-0" class="reference"><a href="#cite_note-named-1" title=""><span>[</span>2<span>]</span></a></sup></p>
<p>Named reference used again <sup id="cite_ref-named_1-1" class="reference"><a href="#cite_note-named-1" title=""><span>[</span>2<span>]</span></a></sup></p>
<div class="references">
<li id="cite_note-0"><b><a href="#cite_ref-0" title="">^</a></b> This is an unnamed reference</li>
<li id="cite_note-named-1">^ <a href="#cite_ref-named_1-0" title=""><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-named_1-1" title=""><sup><i><b>b</b></i></sup></a> This is a named reference</li>

If citation templates are used, they will inject other classes and ids into the HTML output.