Não informado. (1980). Soil and water conservation news. U.S. Department of Agriculture, Soil Conservation Service.
Style de citation Chicago (17e éd.)Não informado. Soil and Water Conservation News. Washington: U.S. Department of Agriculture, Soil Conservation Service, 1980.
Style de citation MLA (8e éd.)Não informado. Soil and Water Conservation News. U.S. Department of Agriculture, Soil Conservation Service, 1980.
Attention : ces citations peuvent ne pas être correctes à 100%.