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Houghton does not use this field.
Item Policy
Use "91" for everything. (Note we no longer code HD items with a Processing Status of "HD" and a Processing ID of "HDEP". The only chnage you make is to the collection code 852 $c in the Holdings record)
Enumeration/Chronology
Continue to use as we did in Aleph. This is important in order that item records for multi-volume works and archival collections sort correctly.
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