As requested on STYLE-1978

The site has linkable artist pages (http://www.jazzmusicarchives.com/artist/miles-davis), which obviously map to artists, and album pages (http://www.jazzmusicarchives.com/album/miles-davis/kind-of-blue), which seem to be somewhat in between release groups and releases: they seem to apply directly to the earliest release of the album but contain info about other versions, and contain reviews for what I must assume is all versions of the album, since I can't find a separate entry for reissues. I think RG is the safest choice here.

They also have linkable genre pages (http://www.jazzmusicarchives.com/subgenre/cool-jazz) but we can't use those yet