"Student of"/"studied under" relationship for authors
I think this is a relationship is common enough to be added as a more specific relationship than "is/was involved with". It's also useful for those studying how authors are connected i.e. who taught who.

there are several others that can also be added/improved. Monkey wants these done in batch so I will repurpose this ticket for all author-author relationships.
I agree that this relationships should be made so it will be included.