Não informado. (1926). Yearbook of agriculture. U.S. Department of Agriculture.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Yearbook of Agriculture. Washington: U.S. Department of Agriculture, 1926.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Yearbook of Agriculture. U.S. Department of Agriculture, 1926.
Πρόσοχή: Οι παραπομπές μπορεί να μην είναι 100% ακριβείς.