Cita APA (7th ed.)

Arnaud Gerkens, J. (1989). Foundation of exploration geographics. Elsevier.

Cita Chicago (17th ed.)

Arnaud Gerkens, J..C.d. Foundation of Exploration Geographics. New York: Elsevier, 1989.

Cita MLA (9th ed.)

Arnaud Gerkens, J..C.d. Foundation of Exploration Geographics. Elsevier, 1989.