Fixed-Length Data Elements & Leader. For original microforms, code MARC fixed field elements for the microform, as instructed by the CEG. Two elements, 008/23 Form of item (“Form” on OCLC) and 008/22 Form of original item (“Orig” on OCLC) are also coded. Both elements are coded because the form of item (e.g., microfiche) is also the form of the original. (CCM:32.2.1g)
Field 007 carries coded data relating to the physical characteristics of the microform. CONSER Standard Record guidelines require only the first two elements: category of material (007/00 or $a: always “h” for microforms) and Specific material designation (007/01 or $b). Some institutions may desire to code all elements, depending on the needs of their users and staff. (CCM:32.2.1g)
007 ## $a h ǂb d ǂd b ǂe f ǂf u--- ǂg b ǂh u ǂi c ǂj a
The preferred source is the title frame (RDA 2.2.2.2). If there is no title frame, an eye-readable header, commonly found on microfiche, may be used as a substitute. If the title on the header is given in an abbreviated form, or, as is the case with most microfilms, if there is no eye-readable header, the container or accompanying material may be substituted as the preferred source.
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