Controlled subject access terms that supplement terms contained in data in the MARC record and provide subject access and links to the classification number or number span in field 153 (Classification Number).
These fields contain established subject access terms from the subject heading systems and thesauri identified in the second indicator (Subject heading system/thesaurus) or in subfield ‡2 (Source of heading or term) and Field 754 contains a topical subject constructed from a faceted vocabulary. Field 753 (Index Term-Uncontrolled) contains uncontrolled index terms, which provide additional access terms, references between terms, and vocabulary control.
For fields 700-751 and 754, guidelines for applying content designators and input conventions are generally not provided in this document. These fields parallel the subject added entry fields, 600-651, and 654 in the bibliographic format. Complete guidelines for using these fields are provided in the MARC 21 Format for Bibliographic Data: fields X00-X30, 600-651, and 654.
Field 748 - Index Term - Chronological [NEW, 2002]