Nawi, A. ., and G. A. N. . Zakaria. “The Impact of Applying Religious Values through Online Problem-Based Learning Among Undergraduate Students: A Quasi-Experimental Study”. International Journal of Learning, Teaching and Educational Research, vol. 18, no. 8, Aug. 2019, pp. 192-13, https://www.ijlter.myres.net/index.php/ijlter/article/view/529.