Supromajakr, Intira, Panruethai Putthongsri, Phromphong Mahapornpong, and Wisitsiri Chusakul. “Strategy Development to Promote Tourism in a Second Tiercity at Chiangkhan, Loei Province”. Dhammathas Academic Journal 22, no. 3 (September 30, 2022): 107–116. accessed January 8, 2026. https://so06.tci-thaijo.org/index.php/dhammathas/article/view/254887.