Columbia subject headings:
Coast defenses--Canada.
World War, 1939-1945--Campaigns--Atlantic Ocean.
World War, 1939-1945--Naval operations, Canadian.
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.
Harvard subject headings:
World War, 1939-1945--Campaigns--Canada
World War, 1939-1945--Naval operations, German
World War, 1939-1945--Naval operations--Submarine
Princeton subject headings:
Coast defenses--Canada.
World War, 1939-1945--Campaigns--Atlantic Ocean.
World War, 1939-1945--Naval operations, Canadian.
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.