If possible, catalogers should work toward submitting a proposal to establish a local term in the appropriate thesaurus. If the term is not eligible for inclusion in an established thesaurus, local terms may be used in 653 as outlined in the Metadata Standards Working Group's Local headings used at Harvard. Do not use 690; 653 is preferred, as it is a standard MARC field retained in the OCLC master record and indexed.
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