units Units

The units of measure in which the size or length of a cited work is expressed (for example, a @units value might record “pages”, “minutes”, “seconds”, or “linear-feet”).
REQUIRED on element: <size>
Value Meaning
Text, numbers, or special characters Names the units of measure in which the size is expressed, for example, “MB”.
Restriction This attribute is required; it must be provided if the element is used.
Tagged Sample

Pages for a cited government report

...
<ref>
 <mixed-citation publisher-type="gov"
  ><person-group person-group-type="author"
   ><string-name><surname>Norman</surname>, 
    <given-names>John C</given-names></string-name>, 
   <aff>Texas Heart Institute, Houston, TX</aff></person-group>. 
  <gov>Report No.: NIH-N01-HV-5-3006-4-VI. Contract No. 
   N01-HV-5-3006</gov>. <source>ALVAD: 1980. A comprehensive 
   final report to NHLI</source>. Vol. <volume>1</volume>. 
  <publisher-loc>Bethesda (MD)</publisher-loc>:
  <publisher-name>National Institutes of Health, National Heart 
   and Lung Institute, Devices and Services Branch</publisher-name>;
  <month>01</month> <year iso-8601-date="1980-01">1980</year>.
  <size units="pages">340</size> p. Available from: NTIS,
  Springfield, VA; PB80-148810</mixed-citation>
</ref>
...