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Houghton does not have a list of mandatory bibliographic resources which should always be cited in 510 fields. Instead, an annotated list of recommended references is maintained; this list is in a state of constant update and expansion.
N.B. "Not in" references, if required, are made placed in a 500 field, not 510. See DCRM(B) , 7B14.3, or DCRMR 9.32.32.1.