Untong, Akarapong, and Mingsarn Kaosa-ard. “Spas Performances Benchmarking and Operation Effifif Iciency”. Asian Journal of Applied Economics 21, no. 1 (May 20, 2016): 1–19. Accessed April 26, 2024. https://so01.tci-thaijo.org/index.php/AEJ/article/view/52142.