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https://[AlmaBaseURL]/view/oai/[institutioncode]/request?verb=ListSetsListRecords&metadataPrefix=marc21&set=[SetName]
This will let you see what populates your new “z” subfield. On the resulting page, search the data by pressing Ctrl+F and search 949. This will take you to a part of each record that lists all the CSU libraries that have the item in the record. If you look at the “z” subfield, and do not see your library code listed, you will need to add a Normalization Rule to clean the data.
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