Gregory, K. J., & Walling, D. E. (1979). Man and environmental processes: A physical geography perspective. Dawson [etc.].
Dyfyniad Arddull ChicagoGregory, K. J., and D. E. Walling. Man and Environmental Processes: A Physical Geography Perspective. Folkestone: Dawson [etc.], 1979.
Dyfyniad MLAGregory, K. J., and D. E. Walling. Man and Environmental Processes: A Physical Geography Perspective. Dawson [etc.], 1979.
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