Columbia subject headings:
Harvard subject headings:
Africa, Central--History.
Africa, East--History.
Ivory trade--Africa, Central--History--19th century.
Ivory trade--Africa, East--History--19th century.
Kasongo Region (Zaire)--History.
Tippu Tip, 1837-1905.
Princeton subject headings:
Africa, Central--Commerce--History.
Africa, Eastern--Commerce--History.
Ivory industry--Africa, Central--History.
Ivory industry--Africa, Eastern--History.
Tippu Tip, 1837-1905.