So I cant find any drop info on them. Do the books only drop from their respective boss (ie cant get a meph book from a d kill)? Which bosses/areas are able to drop them? Are they a nhilithack/baal exclusive? I don't want to waste my time running d to hopefully add one to my collection when he cant drop one (not that running d is not worth it).
Any info and locations where you have found one would be appreciated
