Krabacher, T., Kalipeni, E., & Layachi, A. (2009). Africa (12th ed.). McGraw-Hill.

Krabacher, Thomas, Ezekiel Kalipeni, and Azzedine Layachi. Africa. 12th ed. Boston: McGraw-Hill, 2009.

Krabacher, Thomas, et al. Africa. 12th ed. McGraw-Hill, 2009.