The case of digital resources is an exemplar of an even tighter relationship between instance and holding/item. They are one and the same in the form of file/s in the cloud. Display or use of that file creates an identical item. We may not even create an item record because the instance description includes the 856 which is the path to the shared item described in the "bib" record. Once one includes that "bib" record in the library catalog then the library "holds" that item- it is available to the users.

Michael Mitchell 

-----Original Message-----
From: J. McRee Elrod [mailto:[log in to unmask]] 
Sent: Tuesday, August 27, 2013 1:09 AM
To: Mitchell, Michael
Cc: [log in to unmask]
Subject: Re: [BIBFRAME] BIBFRAME Annotation Model Draft 2

Michael Mitchell posted:

>A holding is an integral part of an instance and a work.
I agree with you that a work can not exist with an instance, and that an instance can not exist without a work.  

But if I understand what a holding is, the other two can exist without a holding.  The records we prepare for electronic publishers and aggregators have no holdings, which is why LAC NUC will not load the records (although why a holding is needed when there is an 856$u URL for the resource, I fail to understand).

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