Oraphan, P., and Jirawan, K. “Estimating benefits of forest ecosystem service to support payments for ecosystem services in Mae Sa Watershed, Chiang Mai, Thailand”. International Journal of Agricultural Technology 15, no. 4 (July 15, 2019): 613–624. accessed November 17, 2025. https://li04.tci-thaijo.org/index.php/IJAT/article/view/8269.