There was a time when US libraries attempted such "multi-ver" (multiple version) records. The practice had its genesis in consolidating print and microform serial runs, particularly in a card catalog environment. The practice did not long survive in an online catalog environment when the modeling for treating different formats became more stringent and the labor overhead for managing multiple records became much lower than it had been for card catalogs. It could and did persist within some local catalogs since the consolidation of print and microform records was manageable and was often seen as a benefit to users who would find holdings consolidated on one record. The death knell for my own institution came with the advent of packages of both e-serials and e-books. The quantity of records involved under these packages were such that it was an insurmountable task to manually reconcile them against the corresponding print records. There was also the issue of ongoing maintenance, since titles would be added to or dropped from such packages as contracts with the package aggregator shifted. With separate records, these could just be incorporated or dropped from the database where "multi-ver" records again would have required manual manipulation (and because neither set of records -- tangible and electronic -- would be a proper subset of the other, and entire update file would have to be managed manually). Meanwhile, in the current catalog modeling, and in RDA built on such modeling, different formats are treated as distinct manifestations warranting their own description.
The above paragraph lays out the theoretical and practical considerations against "multi-ver" or "hybrid" cataloging practices. Having said that, the scope of local digitization efforts may resurface the older dynamics that drove the earlier embrace of such treatments -- the scale of the digitization work may be sufficiently limited to afford manual matching as a more labor efficient effort than crafting distinct records (although cloning the records of the original tangible resource could be fairly straightforward). Even with distinct records for electronic versions of resources, there are still many tangible version records with URLs appended that point to the electronic version, although typically with minimal further modification as was seen in "multi=ver" records (for example, no longer adding another 300 field, 006 field, and 007 field). If such "hybrid" treatment is confined to the local catalog, one is largely free to do as one feels is best for the institution; there won't be cataloging police knocking at one's door. My own institution has such hybrid records for our students' theses from the brief period when we transitioned from strictly tangible to strictly digital formatting -- there were several years when both formats were produced. But short- and long-term costs and benefits should be carefully weighed. In particular, as the scope and scale of digitization efforts expands (and harvesting of data from a digital repository becomes the reality), the "hybrid" treatment may become less tenable, however appealing it may be in the short-term.
John Myers, Catalog & Metadata Librarian
Schaffer Library
Union College
Schenectady, N.Y.
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John Myers
Catalog Librarian
Union College
He/Him/His
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