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Materials published with the main work in different formats such as folded maps, plates, CD-ROMs, etc., issued in a pocket in a book, pocket; pocket-part supplements, errata slips, and ; and errata slips do not need to be recorded in the holdings record. Also, supplements that are not permanently retained do not need to be recorded in the holdings record. This information may be given in the bibliographic record. Optionally, supplement fields in the holdings record may be used to record these items. Either way, it is important to specify the location of such dependent supplemental materials and to distinguish them from supplemental materials which are independently shelved.
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