Não informado. (1980). Soil and water conservation news. U.S. Department of Agriculture, Soil Conservation Service.
Chicago-Zitierstil (17. Ausg.)Não informado. Soil and Water Conservation News. Washington: U.S. Department of Agriculture, Soil Conservation Service, 1980.
MLA-Zitierstil (8. Ausg.)Não informado. Soil and Water Conservation News. U.S. Department of Agriculture, Soil Conservation Service, 1980.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.