907 Overlay code
Add a 907 field. When copy cataloging new materials, there is almost always an order record created in Sierra and a brief bibliographic record for the item already in the system. When copy cataloging you will essentially be replacing the brief record with a new, full record (otherwise known as the process of overlaying). In order to do this, you need to enter the unique Sierra number assigned to the item into a 907 field so the computer will recognize which specific record to replace. In Sierra, the unique number that you use is the bibliographic record number, which will always be preceded by a period and the letter “b” (ex. “.b30442783”).
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907 _ _ .b30442783 <------(always include the period “.” before the letter “b”“b”)
938 Vendor Specific Ordering Data
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