Não informado. (1948). What-s new in crops and soils. American Society of Agronomy.
Chicago-viite (17. p.)Não informado. What-s New in Crops and Soils. Madison, Wis: American Society of Agronomy, 1948.
MLA-viite (8. p.)Não informado. What-s New in Crops and Soils. American Society of Agronomy, 1948.
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