ศุภนัท อ. (2018) “ความเต็มใจจ่ายสำหรับข้าวเสริมแคลเซียม (WILLINGNESS TO PAY FOR CALCIUM-COATED RICE)”, Srinakharinwirot Research and Development Journal of Humanities and Social Sciences. Bangkok, Thailand, 9(18, July-December), pp. 230–240. available at: https://so04.tci-thaijo.org/index.php/swurd/article/view/123782 (accessed: 31 August 2026).