Mustafa, M., M. Shabbir, N. Arshad, A. Naz, M. Waris, and Qurat ul ain. “Level of Fatigue in Traffic Wardens of Lahore; A Cross Sectional Survey”. Pakistan Journal of Medical Research, vol. 59, no. 4, Jan. 2021, pp. 126-9, https://pjmr.org.pk/index.php/pjmr/article/view/131.