667 Fields (Additions and Changes to Authority Records)
1. When adding a "Not the same as" or "Cannot identify with" 667 note to a new authority record, it may be helpful to add a corresponding 667 to the existing record.
2. If a linking reference would normalize to the same form as the heading or another reference on the same record or to the same form as a heading on another record, add an "Old catalog heading" 667 note. It may also be necessary to use this 667 note if the linking reference method of tracing a pre-AACR2 LC heading is not appropriate. Cf. DCM Z1, Introduction, p. 4-6.
See also:
Section II - Additons and Changes to Authority Records
