Cita APA

United States. Department of Agriculture. Natural Resources Conservation Service. (2003). Keys to soil taxonomy. United States Department of Agriculture : Natural Resources Conservation Service.

Citación estilo Chicago

United States. Department of Agriculture. Natural Resources Conservation Service. Keys to Soil Taxonomy. 9th ed. [Washington, D.C.]: United States Department of Agriculture : Natural Resources Conservation Service, 2003.

Cita MLA

United States. Department of Agriculture. Natural Resources Conservation Service. Keys to Soil Taxonomy. 9th ed. [Washington, D.C.]: United States Department of Agriculture : Natural Resources Conservation Service, 2003.

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