I suspect you will find the non-repeatability to be consistent among the NACO nodes (it is true for LC's system, and for the validation routines that check contribution records from NACO nodes). We'll add it to the list of potential changes when we next discuss new elements with the nodes, as it would be best to be consistent with MARC when we can be.
Thanks for finding it,
From: Program for Cooperative Cataloging [mailto:[log in to unmask]] On Behalf Of Bryan Baldus
Sent: Wednesday, February 10, 2016 12:49 PM
To: [log in to unmask]
Subject: 678 repeatability
The MARC 21 Authority documentation for field 678  has a title "678 - Biographical or Historical Data (R)". This seems to indicate that the field should be repeatable, and looking at older documentation (from the 1990s), this does not appear to have changed recently. However, in Connexion if I try validating an authority record with more than 1 678, I get a message "678 - occurs too many times". I didn't see any other mention of the 678 not being repeatable, so I'm wondering why Connexion's validation doesn't allow more than 1 678 to be present.
Thank you for your assistance,
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