X.1 Ship’s Cover and X.1 Ship’s Plans kept by the National Maritime Museum at the Brass Foundry, Woolwich.
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Compton-Hall, Richard, Submarine Warfare – Monsters & Midgets (Poole: Blandford, 1985).
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Everitt, Don, K Boats: Steam-Powered Submarines in World War I (Shrewsbury: Airlife, 1999).
Fitzsimons, Bernard (ed), Warships of the First World War Purnell’s History of the World Wars Special (London: BPC Publishing Ltd, 1973).
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Hackmann, Willem, Seek & Strike: Sonar, Antisubmarine Warfare and the Royal Navy 1914–54 (London: HMSO, 1984).
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Institute of Naval Architects Proceedings for the Year 1937.
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Lenton, H T, and J J Colledge, Warships Of World War II Part Two: Destroyers and Submarines (London: Ian Allan, 1962).
Moss, Michael, and Iain Russell, Range and Vision: The First Hundred Years of Barr & Stroud (Edinburgh: Mainstream, 1988).
Preston, Anthony, Battleships of World War I (New York: Galahad Books, 1972).
___________, and John Batchelor, The First Submarines Purnell’s History of the World Wars Special (London: BPC Publishing Ltd, 1973).
___________, Submarines Since 1919 Purnell’s History of the World Wars Special (London: BPC Publishing Ltd, 1974)
Raven, Alan, and Roberts, John, British Battleships of WWII (Annapolis: Naval Institute Press, 1976).
_____________________, British Cruisers of WWII (London, Arms & Armour Press, 1980).
Rössler, Eberhard, The U Boat – The Evolution and Technical History of German Submarines (London: Arms & Armour Press, 2001).
Rusbridger, James, Who Sank Surcouf? The Truth about the Disappearance of the Pride of the French Navy (London: Century, 1991).
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