Sign of the Serpent: The Key to Creative Physics By Balfour, Mark Books / Paperback Books ISBN: 1853270628 / Publisher: Prism Pr Ltd, December 1990 Price Starting at $169.98 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. Used - Very Good Very Good condition. A copy that may have a few cosmetic defects. May also contain light spine creasing or a few markings such as an owner’s name, short gifter’s inscription or light stamp. $169.98 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 Sign of the Serpent: The Key to Creative Physics