Bear, F. E., & Brown, B. E. (1949). Hunger signs in crops: A symposium. American Society of Agronomy.
Chicago Style aipamenaBear, Firman E., and B E. Brown. Hunger Signs in Crops: A Symposium. U S A: American Society of Agronomy, 1949.
MLA aipamenaBear, Firman E., and B E. Brown. Hunger Signs in Crops: A Symposium. American Society of Agronomy, 1949.
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