Doggar, S., S. Jafri, R. Anwaar, R. Toor, S. Shahbaz, and A. Rehman. “ASSESSMENT OF PRESBYOPIA AMONG MOBILE PHONE AND COMPUTER USERS AT PUNJAB, PAKISTAN”. PAFMJ, Vol. 71, no. 4, Aug. 2021, pp. 1391-94, https://mail.pafmj.org/index.php/PAFMJ/article/view/7313.