Columbia subject headings:
Germany. Kriegsmarine--History--World War, 1939-1945.
World War, 1939-1945--Campaigns--Baltic Sea Region.
World War, 1939-1945--Naval operations, German.
Harvard subject headings:
Germany. Kriegsmarine--History--World War, 1939-1945.
World War, 1939-1945--Campaigns--Baltic Sea Region.
World War, 1939-1945--Naval operations, German.
Princeton subject headings:
Germany. Kriegsmarine--History--World War, 1939-1945.
World War, 1939-1945--Campaigns--Baltic Sea Region.
World War, 1939-1945--Naval operations, German.