SOIL. Soil taxonomy: A basic system of soil classificationfor making and interpreting soil surveys. Departement of Agriculture.
Chicago-referens (17:e uppl.)SOIL. Soil Taxonomy: A Basic System of Soil Classificationfor Making and Interpreting Soil Surveys. U.S: Departement of Agriculture.
MLA-referens (9:e uppl.)SOIL. Soil Taxonomy: A Basic System of Soil Classificationfor Making and Interpreting Soil Surveys. Departement of Agriculture.
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