Não informado. (1907). Proceedings of the American Society of Agronomy. American Society of Agronomy.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Proceedings of the American Society of Agronomy. Washington: American Society of Agronomy, 1907.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Proceedings of the American Society of Agronomy. American Society of Agronomy, 1907.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.