อิ่มประเสริฐ กรัณย์พัฒน์. “Factors of Direct Marketing Influenced Purchasing Behavior of the Consumers in Bangkruai District Nonthaburi Province”. Journal of Humanities and Social Sciences, Rajapruk University 4, no. 1 (May 27, 2018): 122–134. Accessed April 29, 2024. https://so03.tci-thaijo.org/index.php/rpu/article/view/125765.