Brown, G. D., & Ladd, G. T. (1960). The earth: : man's geologic environment. Merrill publishing company.
Chicago Edition CitationBrown, George D., i George T. Ladd. The Earth: : Man's Geologic Environment. Columbus: Merrill publishing company, 1960.
Cita MLABrown, George D., i George T. Ladd. The Earth: : Man's Geologic Environment. Merrill publishing company, 1960.
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