Ainurofiq, A., I. F. Nurcahyo, and R. Yulianto. “PREPARATION, CHARACTERIZATION AND FORMULATION OF NANOCOMPOSITE MATRIX Na-MONTMORILLONITE INTERCALATED MEDIUM MOLECULAR WEIGHT CHITOSAN FOR THEOPHYLLINE SUSTAINED RELEASE TABLET”. International Journal of Pharmacy and Pharmaceutical Sciences, vol. 6, no. 11, Nov. 2014, pp. 131-7, https://journals.innovareacademics.in/index.php/ijpps/article/view/2968.