Teoh, Wei Ping, Swee Yong Chee, Noor Zainab Habib, and Choon Aun Ng. 2022. “An Attempt to Maximize the Use of Used Cooking Oil and Fly Ash in the Production of Green Roofing Tile”. International Journal of Sustainable Construction Engineering and Technology 13 (1): 273-81. https://publisher.uthm.edu.my/ojs/index.php/IJSCET/article/view/11064.