nIn FRBR, expressions can have multiple manifestations; in Variations2 instantiations are unique to a
container.This is a practical consideration:too difficult and time-consuming to identify identical instantiations.
are less abstract than FRBR manifestations,
containing some amount of item-level descriptors.
nFRBR items are copies in
a collection; Variations2 media objects
two differences result from Variations2 focusing exclusively on digital content.FRBR
did not have this focus.