P, S., K. A. M.A, and S. Fuad S.H. “Effect of Shape and Surface Texture of Aggregates During High Intensity Vertical Shaft Impact Autogeneous Crushing”. Malaysian Journal of Science, vol. 21, Dec. 2002, pp. 181-3, https://samudera.um.edu.my/index.php/MJS/article/view/8885.