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Default MARC bibliographic → Instance mappings can be found via the MARC Mappings page.
Holdings data
As with Instances, the native FOLIO format for holdings is not MARC. FOLIO implementers should first decide what format they prefer for holdings data. MARC holdings data can be mapped to Inventory but will need to be edited in another app or tool (such as MARCcat). The FOLIO holdings data are granular enough that basic textual holdings can be generated for export in MARC, but do not include, for instance, captions and patterns that are distinct from enumeration and chronology; and note fields do not include subfields.
Item data
Item records in FOLIO contain standard item-level information. The three-part item state is explained in detail here. NEED SOMETHING ABOUT LOAN RULES & LOCATIONS HERE
Special situations:
Bound-withs - see more information here
Equipment
Statistical codes
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