Gerald W Olson. (1981). Soils and the environment: A guide to soil surveys and their applications. New York: Chapman and Hall.
Παραπομπή Chicago StyleGerald W Olson. Soils and the Environment: A Guide to Soil Surveys and Their Applications. New York: Chapman and Hall, 1981.
Παραπομπή MLAGerald W Olson. Soils and the Environment: A Guide to Soil Surveys and Their Applications. New York: Chapman and Hall, 1981.
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