Chu-Ongsakul, S. “Microeconomic Considerations for A National Health Insurance Policy: ‘Thirty Bat Copayment for All’”. Siriraj Medical Journal, vol. 53, no. 1, Jan. 2001, pp. 43-45, https://he02.tci-thaijo.org/index.php/sirirajmedj/article/view/264998.