APA
Obasanjo O., Orville H., . (1990). The impact of Europe in 1992 on West Africa. New York: Crane Russak.
Chicago
Obasanjo Olusegun, Orville Hans, . 1990. The impact of Europe in 1992 on West Africa. New York: Crane Russak.
Harvard
Obasanjo O., Orville H., . (1990). The impact of Europe in 1992 on West Africa. New York: Crane Russak.
MLA
Obasanjo Olusegun, Orville Hans, . The impact of Europe in 1992 on West Africa. New York: Crane Russak. 1990.