Columbia subject headings:
Harvard subject headings:
Friendly fire (Military science)
Nova Scotia (Ship)
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.
Princeton subject headings:
Friendly fire (Military science)
Nova Scotia (Ship)
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.