Columbia subject headings:
Africa, Sub-Saharan--History--To 1884.
Slave trade--Africa.
Harvard subject headings:
Africa, Sub-Saharan--History--To 1884.
Slave trade--Africa
Princeton subject headings:
Africa, Sub-Saharan--Economic conditions.
Slave trade--Africa, Sub-Saharan--History.
Slavery--Economic aspects--Africa, Sub-Saharan.