Virakornphanich, Prasop. “Effect of Clay Type on Humus Formation from Alfalfa Meal”. Thai Agricultural Research Journal 8, no. 1 (January 1, 1990): 9–16. accessed October 1, 2026. https://li01.tci-thaijo.org/index.php/thaiagriculturalresearch/article/view/242401.