Columbia subject headings:
World War, 1939-1945--Aerial operations.
World War, 1939-1945--Blockades.
Harvard subject headings:
World War, 1939-1945--Aerial operations
World War, 1939-1945--Aerial operations, British
World War, 1939-1945--Blockades
Princeton subject headings:
World War, 1939-1945--Aerial operations, British.
World War, 1939-1945--Blockades.