Seizing the enigma : the race to break the German U-boat codes, 1939-1943 /
Kahn, David,1930-
London : Frontline Books ; Annapolis, Md. : Naval Institute Press,
2012.
Includes bibliographical references (p. [359]-375) and index.
World War, 1939-1945
World War, 1939-1945
World War, 1939-1945