Thanks for the K answer, I'd been looking for it for ages. Not fully sure why one would black out the K one, but I agree that it's most likely. Presumably most people have got the phrase and it's originator. The authors of the books in question form puns, which relate to the phrase in question. If you say the first name of the author of AF and the first part of his surname (run them together) it sounds similar to the first two words of the phrase. The author of VB is a pun on one of the pair of words at the end of the phrase.