Não informado. (2021). Illinois Bulletin. University of Illinois at Urbana-Champaign, Agricultural Experiment Station.
Chicago-viite (17. p.)Não informado. Illinois Bulletin. Urbana, Ill: University of Illinois at Urbana-Champaign, Agricultural Experiment Station, 2021.
MLA-viite (8. p.)Não informado. Illinois Bulletin. University of Illinois at Urbana-Champaign, Agricultural Experiment Station, 2021.
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