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