Othuman Mydin, M. A. “Mechanical and Durability Properties of Foamed Concrete With the Addition of Oil Palm Trunk Fibre”. International Journal of Sustainable Construction Engineering and Technology, vol. 13, no. 1, May 2022, pp. 9-24, https://penerbit.uthm.edu.my/ojs/index.php/IJSCET/article/view/8387.