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The former practice of using 776 field subfield |c Original in records for microfilm reproductions has been discontinued under RDA. Subfield |c Original was used in place of subfield subfields |a, |s, and |t for the title catalog entry of the resource reproduced. Although this method is still described in the version of CCM Module 32 that is in Cataloger's Desktop as of 6/24/19, it is being discontinued. See the CONSER Program's web page for an early draft of the revised 32.3, and the MARC documentation about subfield |c: 76x - 78x Linking Entry Fields.
Subfield |i
CONSER preference seems generally to use the natural language labels "Print version," "Online version," "CD-ROM version," "Microfilm version," etc., in such linking fields, when appropriate. The reason for this may be that these are considered easier for library users to understand. However, there are examples throughout CONSER documentation that instead use relationship designators. For instance, the examples in the draft newly revised CCM 32.3 show a preference for "Microfilm version," but CCM 32.3.3 states that either "Reproduction of (manifestation)" or "Print version" can be used to link from microform reproductions to print originals.
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