The X Factor By Norton, Andre Books / Paperback Books Publisher: Ace Books, January 1967 Price Starting at $43.84 Free Shipping Send to a friend Add to Wishlist Below is a list of products arranged by condition. Select the quantity of the product you desire and click the "Add" button. Collectible - Acceptable Signed Signed Copy Collectible - Acceptable. Reading copy only. Cover detached, but present. In polypropylene bag. Barbara Mertz's signature on front endpage. Barbara G. Mertz Rev Trust custom bookplate on front inside cover. This book formed part of Barbara G. Mertz's personal library at her home in Frederick, Maryland. (science fiction, fantasy) $43.84 1 in Stock at Warehouse Quantity Add Free Shipping to continental U.S. OR $1.00 per item discount if shipped to store. Reviews Goodreads reviews for The X Factor There are not any review yet for this book