Jonathan Rochkind. You’ve been to his blog, or read his comments here or on other blogs, or seen him on mailing lists or in the #code4lib IRC channel. Or perhaps you haven’t. But you should.
There’s been lively discussion about FRBR on mailing lists over the last little while, and Rochkind’s been in it. He posted Why FRBR Entity Model Matters: FRBR Considered as Set Relationships on his blog yesterday, prompted by those list debates. I quote but a few brief snippets of him restating, or re-explaining, the Group 1 entities and their definitions:
I’m going to throw out another way of looking at the FRBR Group 1 entities….
An item is a concrete physical thing in your hand, naturally. That’s straightforward, yes? …
Two items belong to the same manifestation if they are physically identical. Or in the case of digital items that have no physicality, if they are bitwise identical, I guess is the good analog….
Two items belong to the same expression if they are textually identical….
Two items belong to the same work if… well, they belong to the same work.