Lookup by ISBN, OCLCnum, or LCCN
Enhance reference with metadata (can serve as an ISBN looker-upper substitute for Amazon)
Optionally notice an ISBN is for an ebook , figure out a probable ISBN for equivalent print, and replace in referent. xID gives formats, so should be possible. ebook ISBN makes many other services fail, like BorrowDirect or other ISBN-based lookups (HathiTrust maybe)
Lookup by ISBN, OCLCnum, or LCCN
Enhance reference with metadata (can serve as an ISBN looker-upper substitute for Amazon)
Optionally notice an ISBN is for an ebook , figure out a probable ISBN for equivalent print, and replace in referent. xID gives formats, so should be possible. ebook ISBN makes many other services fail, like BorrowDirect or other ISBN-based lookups (HathiTrust maybe)