U-Boat 1936-45 (Type VIIA, B, C and Type VIIC/41): An insight into the design, construction and operation of the most feared German U-boat of World War 2 (Owners' Workshop Manual): Gallop, Alan:
Amazon.com: U-boat
The U-Boat: The Evolution and Technical History of German Submarines: Rössler, Eberhard: 9780304361205: Amazon.com: Books