mohamad adzali, Mohamad hazwan, and Mohd Khairy Burhanudin. “Mechanical and Chemical Properties of Coal Bottom Ash As Sand and Cement Replacement: A Review”. Recent Trends in Civil Engineering and Built Environment, vol. 3, no. 1, July 2022, pp. 96-103, https://penerbit.uthm.edu.my/periodicals/index.php/rtcebe/article/view/3273.