Columbia subject headings:
Airships--Germany.
World War, 1914-1918--Aerial operations, German.
Harvard subject headings:
Airships--Germany--History--20th century.
World War, 1914-1918--Aerial operations, German
World War, 1914-1918--Campaigns--Great Britain
Princeton subject headings:
World War, 1914-1918--Aerial operations, German.