Musafar Hameed, L. B. ., R. . Rasiah, and N. . Mohd Shukor. “Out-of-Pocket Health Expenditure and Catastrophic Effects: Case of Malaysia: Penggunaan Duit Poket Untuk Perbelanjaan Kesihatan Dan Kesan Catastrophic: Kajian Kes Di Malaysia”. Journal of Management and Muamalah , vol. 7, no. 1, June 2017, pp. 55 -67, https://jmm.kuis.edu.my/index.php/jurnal/article/view/66.