Nizar Ismail, K., Sobri Idris, M., Hussin, K., & Azizi Mohd Azizli, K. (2002). The Microstructure of Lightweight Aggregates Made of Pulverised Fuel Ash. Malaysian Journal of Science, 21, 177–179. Retrieved from https://mjes.um.edu.my/index.php/MJS/article/view/8884