Saleem Aziz, Majed, Ahmad Nurulazam Md. Zain, Mohd Ali Bin Samsudin, and Salmiza Binti Saleh. 2014. “The Effects of Problem-Based Learning on Self-Directed Learning Skills Among Physics Undergraduates”. International Journal of Academic Research in Progressive Education and Development 3 (1). https://ijarped.com/index.php/journal/article/view/154.