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When the books are shipped, B&T will send a file of item records with full bibs with OCLC numbers. These are loaded with m2btab.b (L), the default loader in Data Exchange. This will try to match on Bib Util number. If there is no Bib Util match, then it will insert a new record. If there is a BIB UTIL match, it will overlay the bib record.
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