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FAQ
Deciphering NLM's Identifier Numbers Used in OCLC

Question: How do I determine which identifier number for serials records is used in OCLC?
Answer:

In the past, NLM added the TCN/SERLINE UI/SEQ to the OCLC 069 first indicator 1 field (NLM serial control number). The Unique ID from other NLM systems was added to the OCLC 069 first indicator 0 field (NLM CATLINE or AVLINE citation number). The OCLCMARC SERHOLD conversion program used the NLM serial control number.

From March through mid-May 1999, NLM added the NLM Unique ID to both the NLM serial control number (069 first indicator 1) and the NLM CATLINE or AVLINE citation number (069 first indicator 0). Beginning in mid-May 1999, NLM began adding the NLM Unique ID to only the NLM CATLINE or AVLINE citation number. When completed, the new OCLCMARC SERHOLD conversion program will be able to identify the appropriate NLM Unique ID from either the NLM serial control number or the NLM CATLINE or AVLINE citation number.

To summarize, in OCLC the NLM Unique ID for Serials may be found in:

For libraries that wish to add an NLM Unique ID to an OCLC record, please add the appropriate number to the 069 first indicator 0.

Related Questions:
Cataloging and Bibliographic Questions

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http://www.nlm.nih.gov/services/cat_oclcui.html

Last updated: 06 May 2004
First published: 01 January 1998
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