Scapa Flow: The Defences of Britain?s Great Fleet Anchorage 1914-45 - Angus Konstam
Oxford: Osprey Publishing, Paperback, 2009, Paperback £9.80
U-Boat Bases and Bunkers 1941-45 - Gordon Williamson
Oxford: Osprey Publishing, Paperback, 2003, Paperback £10.50U-Boat Bases and Bunkers 1941-45 - Gordon Williamson
Oxford: Osprey Publishing, Paperback, 2003, Paperback £11.80