H. Shukor, M. Sahaid Kalil, N. Anuar, A. Abdul Hamid, and A. Hanan, “Small Review: Strategies for Palm Kernel Cake (PKC) As a New Potential Substrate in Biofuel Production”, Int. J. Adv. Sci. Eng. Inf. Technol., vol. 3, no. 3, pp. 248–255, Jun. 2013.