2.36 Editing MARC 21 Bibliographic Variable Fields
The variable fields are documented by the Library of Congress at
http://lcweb.loc.gov/marc. The purpose of this documentation is
to state the behavior of this software, as well as to state the
importance of particular fields to this software.
Each bib must have a field 245, Title Statement, with a valid
subfield a, Title. No other tag or subfield is needed for a bib.
Therefore, every library resource can go into the catalog: books,
journals, URLs, VCRs, room keys, etc.
