Não informado. (1919). Journal of Farm Economics. American Farm Economic Association.
Chicago-referens (17:e uppl.)Não informado. Journal of Farm Economics. Menasha, Wis: American Farm Economic Association, 1919.
MLA-referens (8:e uppl.)Não informado. Journal of Farm Economics. American Farm Economic Association, 1919.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.