Russell Francis. The Secret War

Time-Life Books, 1982. — 208 p.Text and photographic essays tell of espionage in World War II: the spies, spy networks, codes, electronic eavesdropping, weapons and hoaxes used by both sides. This book is a very good overview of WWII spies. Included are great propaganda posters in color, photos of spies, activities, and equipment, and great narratives of Axis and Allies spies and covert operations.