>> Because :creator, :composer and the agent involved are all objects of the triples, they could easily be literals or URIs (and even those URIs can't possibly always be BIBFRAME ones).
>I don't understand the last part of this statement - what would it mean for the URIs to be 'BIBFRAME' ones in this case? I think we could expect a set of data to be self-sufficient (i.e. to coin URIs where required and not rely on external entities if the desire is to avoid this)
What I meant on this point was that BIBFRAME may very well start with bf:creator and a bf:contributor relationship URIs, but then further define, say, URIs to cope with the standard RDA relationships from Appendix I (which I am sure you can go and quick check right now... e.g bf:enactingJurisdiction), but if libraries starting using their own, will BIBFRAME really keep up to date with those too? If BIBFRAME is meant also to cover non-RDA/AACR2 data then there is a potentially huge number of relationships from other schemes that would either be lost of subsumed into BIBFRAME terminology.