Thitanuwat, Bussarakam, and Manaporn Wongsoonthornchai. 2021. “Estimation of Nitrogen Loading to Surface Water from Agriculture Based Area and Its Application for Water Pollution Mitigation: 10.32526/Ennrj/19/2020239”. Environment and Natural Resources Journal 19 (3). Nakhon Pathom, Thailand:230-38. https://ph02.tci-thaijo.org/index.php/ennrj/article/view/242099.