Columbia subject headings:
Caspian Sea Region--History--20th century--Sources.
World War, 1914-1918--Iran--Caspian Sea Region--Sources.
Harvard subject headings:
Caspian Sea Region--History--20th century--Sources.
World War, 1914-1918--Iran--Caspian Sea Region--Sources.
Princeton subject headings:
Caspian Sea Region--History--20th century--Sources.
World War, 1914-1918--Iran--Caspian Sea Region--Sources.