Não informado. (1924). Agricultural Progress. Agricultural Education Association.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Agricultural Progress. London: Agricultural Education Association, 1924.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Agricultural Progress. Agricultural Education Association, 1924.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.