ทองรอด ชัยฤทธิ์. 2017. “Influential Factors Effecting Decisions of Utilize Natural Gas Vehicles (NGV): A Case Study of Privare Cars in Samutprakarn Province”. Ph.D. In Social Sciences Journal 1 (1):23-31. https://so05.tci-thaijo.org/index.php/phdssj/article/view/74695.