Chan, Chee Ming, and S.S. Ch'ng. “Preliminary Study of S-Wave Velocity and Unconfined Compressive Strength of Cement- Palf Stabilised Kaolin”. International Journal of Integrated Engineering, vol. 2, no. 2, Sept. 2011, https://penerbit.uthm.edu.my/ojs/index.php/ijie/article/view/206.