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Occasionally a multi-part item will be shelved in two or more locations, e.g., text and atlas shelved separately. In such cases, create separate holdings records for the parts in each shelving location, i.e. with a different 852 subfield c or m. The 853/863 and 854/864 fields in each holdings record should reflect only the parts therein. The following example is for a 4-volume text with oversize 2-volume atlas shelved separately:
852 8_ |c $$c GEN |h $$h Typ 815.26.2570
853 20 |8 $$8 1 |a $$a v.
863 40 |8 $$8 1.1 |a $$a 1-4
852 8_ |c GEN |c PF |h $$c PF $$h Typ 815.26.2570
854 03 |8 $$8 1 |a $$a (unit) |b $$b v.
864 41 |81$8 1.1 |a $$a atlas |b $$b 1-2