สุขเกษมม., and กาฬสมุทร์น. “The Sustainable Creative Tourism Management: World Heritage Site-Cultural Heritage Alive: A Case Study of Historical Town of Sukhothai and Associated Historic Towns”. RMUTI JOURNAL Humanities and Social Sciences, Vol. 5, no. 1, June 2017, pp. 160-78, https://so05.tci-thaijo.org/index.php/RMUTI_SS/article/view/189670.