S. N. Razali, F. Shahbodin, M. H. Ahmad, and H. A. Mohd Noor, “Measuring Validity And Reliability of Perception of Online Collaborative Learning Questionnaire Using Rasch Model”, Int. J. Adv. Sci. Eng. Inf. Technol., vol. 6, no. 6, pp. 966–974, Dec. 2016.