English, B. C., Alt, K. F., & Heady, E. O. (1982). A documentation of the resources conversation act's assessment model of regional agricultural production, land and water use, and soil loss. Ames, Iowa: Center for Agricultural and Rural Development. Iowa State University.
Παραπομπή Chicago StyleEnglish, Burton C., Klaus F. Alt, and Earl O. Heady. A Documentation of the Resources Conversation Act's Assessment Model of Regional Agricultural Production, Land and Water Use, and Soil Loss. Ames, Iowa: Center for Agricultural and Rural Development. Iowa State University, 1982.
Παραπομπή MLAEnglish, Burton C., Klaus F. Alt, and Earl O. Heady. A Documentation of the Resources Conversation Act's Assessment Model of Regional Agricultural Production, Land and Water Use, and Soil Loss. Ames, Iowa: Center for Agricultural and Rural Development. Iowa State University, 1982.