This is a metadata element intended to hold the series number in the rare case where a single journal has multiple volumes of the same number.
The rare example of this is a publisher reissuing a journal and restarting the volume number with “1”. Duplicate volume numbers would then exist and need to be differentiated in citations. A publisher may add a series number to the volume and <volume-series> has been created to hold such a number.
<volume-series> should hold the number or name of the series of the volume’s series (“1” for the original numbering and “2” for the re-numbering), while <volume> holds the number of the volume within that series (for example, “519”).
<!ELEMENT volume-series (#PCDATA %volume-series-elements;)* >
Text, numbers, or special characters, zero or more
<element-citation>, <mixed-citation>, <product>, <related-article>, <related-object>
No sample is available at this time.