<r>For good submarine history in WW2, with main accent on tech details, see E.Bagnasco, Submarines of the world war 2. Its in same hardcover as M.J.Whitley's Destroyers of WW2, Cruisers of WW2 and Battleships of WW2. I am not 100 % sure on the english title of the book, as I own it in german. <br ...