Arnaud Gerkens, J. (1989). Foundation of exploration geographics. Elsevier.
Cita Chicago Style (17a ed.)Arnaud Gerkens, J..C.d. Foundation of Exploration Geographics. New York: Elsevier, 1989.
Cita MLA (9a ed.)Arnaud Gerkens, J..C.d. Foundation of Exploration Geographics. Elsevier, 1989.
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