Walker, John B. A Guide to American Airplanes, 56 Airplanes Illustrated in Full Color. Racine Wisconsin, Whitman Publ Co., 1940. 64pp, color artist illus, small pocket size 6x4", stiff card covers. Includes Highlights of Aviation History, pictures of aviation trophies, charts of record flights. Nice pre-WWII picture of aviation. Good plus.