Khan, T. S., M. Jehangir, A. Niwaz, M. M. Khan, M. Shahzad, and M. S. Khan. 2018. “Statistical Approach: Understanding the Effects of Preview, Question, Read, Reflect, Recite, Review (PQ4R) on Academic Achievement of Students in English”. The Nucleus 55 (2):61-65. http://202.83.167.189/index.php/Nucleus/article/view/246.