Tawfik, Andrew A, Joi L. Moore, Zhenyu He, and Ngoc Vo. “Human-Computer Interaction Factors in Designing Educational Video Games”. Current Issues in Education 15, no. 3 (September 7, 2012). Accessed September 16, 2019. https://cie.asu.edu/ojs/index.php/cieatasu/article/view/987.