Não informado. (2007). Report of the Iowa Agricultural Experiment Station for de two years. Agricultural Experiment Station.
Chicago-viite (17. p.)Não informado. Report of the Iowa Agricultural Experiment Station for De Two Years. Ames, Iowa: Agricultural Experiment Station, 2007.
MLA-viite (8. p.)Não informado. Report of the Iowa Agricultural Experiment Station for De Two Years. Agricultural Experiment Station, 2007.
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