Collected Papers on Mathematics, Logic, and Philosophy Gottlob Frege ISBN: 978-0-631-12728-4 Hardcover 422 pages January 1991, Wiley-Blackwell US $57.95 Add to Cart This price is valid for United States. Change location to view local pricing and availability. This is a Print-on-Demand title. It will be printed specifically to fill your order. Please allow an additional 5-6 days delivery time. The book is not returnable.