Operation Sea Lion: The Projected Invasion of England in 1940 -- An Account of the German Preparations and the British Countermeasures

323 pp. Illustrated with black-and-white photographs and woodcut illustrations. Operation Sea Lion, also written as Operation Sealion (German: Unternehmen Seelöwe), was Nazi Germany's code name for the plan for an invasion of the United Kingdom during the Battle of Britain in the Second World War.