Kheara, Varin, Suthee Chantrapunth, and Chun Che Fung. “Protection Motivation Theory Model for Smartphone User”. NKRAFA Journal of Humanities and Social Sciences 5 (August 2, 2018): 50–59. accessed September 2, 2026. https://so04.tci-thaijo.org/index.php/KANNICHA/article/view/137754.