Não informado. (2012). Purdue Agricultures Magazine. Purdue University, College of Agriculture.
Chicago-viite (17. p.)Não informado. Purdue Agricultures Magazine. West Lafayette, Ind: Purdue University, College of Agriculture, 2012.
MLA-viite (8. p.)Não informado. Purdue Agricultures Magazine. Purdue University, College of Agriculture, 2012.
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