Columbia subject headings:
Africa, French-speaking West--History--Congresses.
Ghana (Empire)--History--Congresses.
Mali (Empire)--History--Congresses.
Songhai Empire--History--Congresses.
Harvard subject headings:
Africa, French-speaking West--History--Congresses.
Ghana (Empire)--History--Congresses.
Mali (Empire)--History--Congresses.
Songhai Empire--History--Congresses.
Princeton subject headings: