This Tag Set has a single general purpose element <size> for recording the number of pages in a book, the showing time of a film, the number of kilo/mega/tera-bytes in a dataset, or any other measurement of size, length, or extent that may be recorded for a cited work. The @units attribute should be used whenever possible to state the unit of measure, such as “page”, “minute”, “paragraph”, “MB”, etc., which is typically given in the singular (“page” rather than “pages”).
The <page-count> is a metadata element in the description of the work that records similar page-size information for the work rather than for cited material. The <size> and <page-count> are modeled very differently. The size element is assumed to contain the textual value of the size
while the page count element is an EMPTY element that stores its value in the @count attribute:
In element-style citations (<element-citation>), the units can be handled in the following ways. If the @units attribute value has been tagged consistently, the text can be generated on display and does not have to be included in the tag:
If the publisher or archive does not wish to generate text based on the attribute or the attributes have not been tagged consistently, the text can be included in the <size> tag:
<size units="page">256 pages</size>