Não informado. (2020). Research Progress Report. Purdue University, Agricultural Experiment Station.
Chicago-referens (17:e uppl.)Não informado. Research Progress Report. Lafayette, Ind: Purdue University, Agricultural Experiment Station, 2020.
MLA-referens (8:e uppl.)Não informado. Research Progress Report. Purdue University, Agricultural Experiment Station, 2020.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.