Abdul Rahim, S., W. M. Razi Idris, I. B.S, M. B. Gasim, R. Omar, Z. Ali Rahman, M. Md. Tan, and B. Musta. “Composition and Distribution Patterns of Major and Trace Elements in Gradually Weathered Andesite Rock from FELDA Jengka 4, Pahang, Malaysia”. Malaysian Journal of Science, vol. 27, no. 1, Apr. 2008, pp. 153-62, https://juku.um.edu.my/index.php/MJS/article/view/7947.