National food review Economics, Statistics, and Cooperatives Service, U.S. Department of Agriculture. [electronic resource].
Chicago-referens (17:e uppl.)National Food Review Economics, Statistics, and Cooperatives Service, U.S. Department of Agriculture. [electronic Resource].
MLA-referens (9:e uppl.)National Food Review Economics, Statistics, and Cooperatives Service, U.S. Department of Agriculture. [electronic Resource].
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.