Columbia subject headings:
Airplanes--Fuel.
Explosives, Military.
Gases, Asphyxiating and poisonous.
World War, 1939-1945--Germany.
Harvard subject headings:
Princeton subject headings:
Airplanes--Fuel.
Explosives, Military.
Gases, Asphyxiating and poisonous.
World War, 1939-1945--Germany.