Cita APA (7a ed.)

Gregersen, E. A., & LaRuffa, A. L. (1977). Language in Africa: An introductory survey. Gordon and Breach.

Cita Chicago Style (17a ed.)

Gregersen, Edgar A.., y Anthony L. LaRuffa. Language in Africa: An Introductory Survey. New York ; Paris ; London: Gordon and Breach, 1977.

Cita MLA (9a ed.)

Gregersen, Edgar A.., y Anthony L. LaRuffa. Language in Africa: An Introductory Survey. Gordon and Breach, 1977.