Columbia subject headings:
Soviet Union--Defenses.
World War, 1939-1945--Aerial operations, German.
World War, 1939-1945--Campaigns--Soviet Union.
Harvard subject headings:
Soviet Union--Defenses.
World War, 1939-1945--Aerial operations, German.
World War, 1939-1945--Campaigns--Soviet Union.
Princeton subject headings:
Soviet Union--Defenses.
World War, 1939-1945--Aerial operations, German.
World War, 1939-1945--Campaigns--Soviet Union.