Klages, K. H. W. (1947). Ecological Crop Geography. The Macmillan Company.
Cita Chicago Style (17a ed.)Klages, Karl H. W. Ecological Crop Geography. New York: The Macmillan Company, 1947.
Cita MLA (9a ed.)Klages, Karl H. W. Ecological Crop Geography. The Macmillan Company, 1947.
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