Columbia subject headings:
Hitler, Adolf, 1889-1945.
Roosevelt, Franklin D. (Franklin Delano), 1882-1945.
World War, 1939-1945--Naval operations, American.
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.
Harvard subject headings:
Hitler, Adolf, 1889-1945
Roosevelt, Franklin D. (Franklin Delano), 1882-1945
World War, 1939-1945--Naval operations, American.
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.
Princeton subject headings:
Hitler, Adolf, 1889-1945.
Roosevelt, Franklin D. (Franklin Delano), 1882-1945.
World War, 1939-1945--Naval operations, American.
World War, 1939-1945--Naval operations, German.
World War, 1939-1945--Naval operations--Submarine.