McKenzie, G. D., & Utgard, R. O. Man and his physical environment: Readings in environmental geology.
Chicago-viite (17. p.)McKenzie, Garry D., ja Russell O. Utgard. Man and His Physical Environment: Readings in Environmental Geology.
MLA-viite (9. p.)McKenzie, Garry D., ja Russell O. Utgard. Man and His Physical Environment: Readings in Environmental Geology.
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