(1968). Problems in African history. Prentice-Hall.
Chicago-čujuhus (17. p.)Problems in African History. Englewood Cliffs: Prentice-Hall, 1968.
MLA-čujuhus (9. p.)Problems in African History. Prentice-Hall, 1968.
Muitte dárkkistit čujuhemiid riektatvuođa, ovdal go geavahat daid iežat deavsttas.