Malek, F., H. Nornikman, and O. Nadiah. “Pyramidal Microwave Absorber Design from Waste Material Using Rice Husk and Rubber Tire Dust”. Journal of Telecommunication, Electronic and Computer Engineering (JTEC), vol. 4, no. 1, June 2012, pp. 23-30, https://jtec.utem.edu.my/jtec/article/view/471.