T. S. Khan, M. Jehangir, A. Niwaz, M. M. Khan, M. Shahzad, and M. S. Khan, “Statistical Approach: Understanding the Effects of Preview, Question, Read, Reflect, Recite, Review (PQ4R) on Academic Achievement of Students in English”, The Nucleus, vol. 55, no. 2, pp. 61–65, Oct. 2018.