Ueangsawat, Kanita, Surin Nilsamranchit, and Attachai Jintrawet. 2016. “Comparison of Estimation Methods for Daily Reference Evapotranspiration under Limited Climate Data in Upper Northern Thailand”. Environment and Natural Resources Journal 14 (2). Nakhon Pathom, Thailand:10-23. https://ph02.tci-thaijo.org/index.php/ennrj/article/view/69510.