Phongpan, Sakorn. “Use of Inhibitors to Improve the Efficiency of Urea Fertilizer in Lowland Rice Field”. Thai Agricultural Research Journal 15, no. 2 (March 23, 1997): 145. accessed September 30, 2026. https://li01.tci-thaijo.org/index.php/thaiagriculturalresearch/article/view/236569.