Nugroho, K.A., and M.C.D. Kurnianingtyas. “The Effect of Fidgeting On Student Concentration Levels”. International Journal of Industrial Engineering and Engineering Management 1, no. 2 (December 7, 2019): 17–24. Accessed September 1, 2024. https://ojs.uajy.ac.id/index.php/IJIEEM/article/view/3062.