This is a complete set. I'm selling it to organize my belongings due to a move. I bought all of them new at the time, and they don't seem to have any yellowing. Many of them are first editions. Volumes 1, 2, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, and 24 are first editions.