Não informado. (1949). Progressive agriculture in Arizona. University of Arizona, College of Agriculture.
Chicago-referens (17:e uppl.)Não informado. Progressive Agriculture in Arizona. Tucson, Ariz: University of Arizona, College of Agriculture, 1949.
MLA-referens (8:e uppl.)Não informado. Progressive Agriculture in Arizona. University of Arizona, College of Agriculture, 1949.
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