BRIGGS, D. (1981). Sources and methods in geogaphy: Soils. Butterworths.
Chicago-viite (17. p.)BRIGGS, David. Sources and Methods in Geogaphy: Soils. London: Butterworths, 1981.
MLA-viite (9. p.)BRIGGS, David. Sources and Methods in Geogaphy: Soils. Butterworths, 1981.
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