Malek S.N, A., L. H.S, M. N, M. Ali N.A, and P. N. “Investigation on The Stem Bark of Trema Orientalis”. Malaysian Journal of Science, vol. 24, no. 1, Jan. 2005, pp. 113-9, http://ijie.um.edu.my/index.php/MJS/article/view/8942.