Borhan, J. T., and C. Z. Saari. “The Principle of Al-Takaful (Collective Responsibility) In Islam and Its Practice in the Operations of Syarikat Takaful Malaysia Berhad”. Jurnal Usuluddin, vol. 17, June 2003, pp. 33-56, https://mjlis.um.edu.my/index.php/JUD/article/view/4069.