<volume>
The <volume>
element contains the book's volume number, such as "2" to represent
Volume 2.
See appendix for information about this element in OASIS document type shells.
- topic/data bookmap/volume
<bookmeta>
<bookid><volume>2</volume></bookid>
</bookmeta>
The following attributes are available on this element: Data element attributes group, Link relationship attribute group, Universal attribute group, and outputclass.