Well, how about books on Christian philosophy?
This one’s a little more irritating, because the writer people are thinking of with regards to this question is John Sanford. Note the lack of a “d” in the middle of the last name. About half the reviews of the author’s books spell his name as “Sanford”, and even Amazon Dot Com gets it wrong, including links to John Sandford and John Sanford (the Christian philosophy writer) in the listings for the Prey novels, despite the two being completely different.