Tankasem, Phongphan, Wichuda Satiennam, and Thaned Satiennam. 2015. “An evaluation of speed limit measure: A case of the Mittraphap highway passing through Khon Kaen city”. Engineering and Applied Science Research 42 (2):135-44. https://ph01.tci-thaijo.org/index.php/easr/article/view/34873.