Additional information tied to a particular location in the text, which is not considered to be part of the body of the text, but is a note instead of, in addition to, as a source for, or as a commentary on either some body text or on an element in the metadata such as an author


In print, footnotes are traditionally displayed at the bottom of a printed page or in a list at the end of a book or a book component such as a chapter (<fn-group>); each footnote reference is marked by a number or symbol, and the text of the footnote is prefixed by the same number or symbol to help the reader associate the text with its reference(s). On screen, footnotes may appear as clickable icons, in a separate pop-up window, in a list with links at the end of the book or book component (<fn-group>), or in a separate footnote area.

A reference to a <fn> is made with the <xref> element.

To describe a footnote that is not in the same language as the original document (for example, a Latin or Greek footnote for a document in English), use the @xml:lang attribute on the footnote.

Conversion Note: When footnotes are grouped at the end of a book (or book component such as a chapter), wrap them in a <fn-group> and use an <xref> element in the text, as usual, to tie each footnote in the list to a particular location in the text.


fn-type Type of Footnote
id Identifier
symbol Symbol
xml:lang Language

Related Elements

A footnote <fn> usually contains material that cannot stand alone: material that is related to a word, phrase, or paragraph already in the basic textual material.

Content Model

<!ELEMENT  fn           %fn-model;                                   >

Expanded Content Model

(label?, (p)+)


The following, in order:

This element may be contained in:

<aff>, <alt-title>, <article-title>, <attrib>, <author-notes>, <bold>, <book-title>, <chem-struct>, <collab>, <collection-name>, <comment>, <def-head>, <fn-group>, <italic>, <kwd>, <license-p>, <meta-value>, <monospace>, <named-content>, <overline>, <p>, <product>, <roman>, <sans-serif>, <sc>, <speaker>, <strike>, <styled-content>, <sub>, <subtitle>, <sup>, <table-wrap-foot>, <td>, <term>, <term-head>, <th>, <title>, <trans-subtitle>, <trans-title>, <underline>

Example 1

In the footer of a table:

<table-wrap id="bid.269">
<title>Files on the taxonomy FTP site.</title>
<fn symbol="a" id="mul2">
<p>For non-UNIX users, the file taxdmp.zip includes the 
same (zip compressed) data.</p>

Example 2

In a footnote group:

<fn><p>Competing interests: None declared.</p></fn>