Juffrizal, K., M. Nidzamuddin, C. Tan, Z. Zulfattah, M. Shaifuddin, and R. Aizat. “Design and Efficiency Studies on Skimmers in an Active Grease Trap”. Journal of Engineering and Technology (JET), vol. 5, no. 1, June 2014, pp. 121-34, https://jet.utem.edu.my/jet/article/view/132.