N. Mohd Zaid, F. S. Yaacob, N. A Shukor, M. N. H. Mohd Said, A. H. Musta’amal, and D. Rahmatina, “Integration of Peer Instruction in Online Social Network to Enhance Higher Order Thinking Skills”, Int. J. Interact. Mob. Technol., vol. 12, no. 8, pp. pp. 30–40, Dec. 2018.