Shafii, Z., S. Mohd Sapian, and M. Ahmad. “Using Activity Based Approach and Analytical Hierarchy Process in Comprehensive Islamic Financial Plan Construction”. The Journal of Muamalat and Islamic Finance Research, vol. 5, no. 1, Jan. 2008, pp. 155-82, https://jmifr.usim.edu.my/index.php/jmifr/article/view/80.