Music Library Association Best Practices for identifier for expression

Record the element in bibliographic records, if feasible and readily ascertainable, for each instance of an International Standard Recording Code (ISRC) associated with a specific audio recording. Note that ISRCs, when present, are assigned separately to each recorded expression on an album, not to the album itself.

Record the element for other types of identifier if readily available and if deemed useful for identification or selection.

In MARC: For an ISRC: Record as an identifier using field 024 (first indicator 0) subfield $a.

Cataloger's judgment.

Apply the option for identifiers present in the resource itself.

In MARC: For an ISRC: Apply the option by using first indicator 0 in field 024.