Columbia subject headings:
Songhai (African people)--History.
Songhai (African people)--Social conditions.
Zarma (African people)--History.
Zarma (African people)--Social conditions.
Harvard subject headings:
Songhai (African people)--History.
Songhai (African people)--Social conditions.
Zarma (African people)--History.
Zarma (African people)--Social conditions.
Princeton subject headings:
Songhai Empire--Social life and customs.
Zarma (African people)--Social life and customs.