Names one of the months of the year, such as “July” or “07”.


Used within both article metadata and citations (<element-citation> and <mixed-citation>), this element may contain the textual name of a month (“December”), a month-name abbreviation (“Dec”), or a numeric month (“12”). Numeric months are best practice for archives who wish to regularize their data.

Best Practice: For ease in comparisons and searching, many archives prefer that months be converted to numeric value of the following form:


Related Essay: For a discussion on the use of <month>, see Dates in Citations.


content-type Type of Content
specific-use Specific Use
xml:lang Language

Related Elements

Within citations (<element-citation> and <mixed-citation>), this element is used to name the month of publication. The elements <year>, <date>, <day>, <month>, and <season> may all be used to describe the date a cited resource was published. Other dates inside a citation, such as a copyright date, the date on which the author accessed the resource, or a withdrawal date, should be tagged using <date-in-citation> with the @content-type attribute used to name the type of date (copyright, access-date, time-stamp, etc.).

Content Model

<!ELEMENT  month        (#PCDATA)                                    >


Text, numbers, or special characters

This element may be contained in:

<access-date>, <conf-date>, <date>, <date-in-citation>, <element-citation>, <mixed-citation>, <nlm-citation>, <product>, <pub-date>, <related-article>, <related-object>, <std>, <string-date>

Example 1

In an element-style bibliographic reference (punctuation and spacing removed):

<element-citation publication-type="book" publication-format="web">
<source>Fact sheet: AIDS information resources</source>
<publisher-loc>Bethesda (MD)</publisher-loc>
<publisher-name>National Library of Medicine
<year iso-8601-date="2002-05-02">2003</year>
<date-in-citation content-type="updated"
iso-8601-date="2005-07-14">updated 2005 Jul 14</date-in-citation>
<date-in-citation content-type="access-date"
iso-8601-date="2006-11-15">cited 2006 Nov 15</date-in-citation>
<size units="screens">[about 3 screens]</size>
<comment>Available from:

Example 2

In a mixed-style bibliographic reference (punctuation and spacing preserved):

<mixed-citation publication-type="book" publication-format="web">
<source>Fact sheet: AIDS information resources</source>
[Internet]. <publisher-loc>Bethesda
(MD)</publisher-loc>: <publisher-name>National
Library of Medicine (US)</publisher-name>;
<year iso-8601-date="2003-05-02">2003</year> <month>May</month>
<day>2</day> [updated <date-in-citation content-type="updated"
iso-8601-date="2005-07-14">2005 Jul 14</date-in-citation>;
cited <date-in-citation content-type="access-date"
iso-8601-date="2006-11-15">2006 Nov 15</date-in-citation>].
<size units="screens">[about 3 screens]</size>. Available from:

Example 3

<article-id pub-id-type="pmid">...</article-id>
<aff id="StLukes">...</aff>
<pub-date pub-type="pub" iso-8601-date="1999-03-27">
<date date-type="accepted" iso-8601-date="2001-01-29">
<copyright-statement>Copyright &#x00A9; 1999, British
Medical Journal</copyright-statement>
<copyright-holder>British Medical Journal</copyright-holder>
<p>To examine the effectiveness of day hospital
attendance in prolonging independent living for
elderly people.</p>