1. Fine Arts Department (FAD). 2013. Si Satchanalai Historical Parks (in Thai). [Online]. Available: http://www.finearts.go.th/archae/parameters/km/item/อุทยานประวัติศาสตร์ศรีสัชนาลัย.html#.
2. United Nations Educational, Scientific, and Cultural Organization (UNESCO). 2017. Historic Town of Sukhothai and Associated Historic Towns. [Online]. Available: http://whc.unesco.org/en/list/574/.
3. Association of Southeast Asian Nations (ASEAN). 2014. UNESCO World Heritage Sites. [Online]. Available: http://www.aseantourism.travel/explore/sub/culture-and-heritage/unesco-world-heritage-sites.
4. See: Kagan, S. 2009. Kagan Cooperative Learning. Kagan Publishing, San Clemente, CA.
5. Nielsen, J. and Budiu, R. 2012. Mobile Usability. Pearson Education, Berkeley, CA.