an Entity references as follows:
German submarine U-591 was a Type VIIC U-boat built for Nazi Germany's Kriegsmarine for service during World War II.She was laid down on 30 October 1940 by Blohm & Voss, Hamburg as yard number 567, launched on 20 August 1941 and commissioned on 9 October 1941 under Kapitänleutnant Hans-Jürgen Zetzsche.