...
Whenever possible the guide/index to a microform set should be added to the bibliographic record for the set. If, in a cataloger’s best judgement, the guide/index is better served by an individual bibliographic record, linking fields must be added to ensure mutual discovery. For example, if the guide was not originally issued as part of the microform set, or was created and published by a different entity, perhaps it should probably not be included on the same bibliographic record.
...