The author was a U-boat commander in 1940 and 1941. He
then served as Staff Officer (Operations) to the Flag
Officer Commanding U-boats for the remainder of WWII. The
book was written (from the perspective of the German
Command) under the auspices of the US Navy Dept and the
British Admiralty. 3 Vols in 1; Vol 1 covers Aug 1939-Dec
1940; Vol 2 Jan 1941-May 1943; Vol 3 June 1943-May 1945.
Strategy, technological change, SIGINT, OP Requirements,
tactics and weapons. This edition has an introduction by Lt
Cdr A J Withers RN. The separate folder contains 5 sheets of
32 colour diagrams.