Supamard Panichsakpatana. “Utilization of Effluent from Biogas Production as Nitrogen Source for Guinea Grass (Panicum maximum Jacq.) Grown on Kamphaeng Saen Soil”. Agriculture and Natural Resources 29, no. 2 (June 30, 1995): 182–192. accessed September 17, 2026. https://li01.tci-thaijo.org/index.php/anres/article/view/241314.