Dilshad, M. A., S. Sarwar, F. Aslam, A. Shabbir, S. Rasool, and G. un-N. Tayyab. “Risk of Covid-19 Infection During endoscopy: Efficacy of Personal Protective Equipment (PPE) in Protecting Health Professionals”. Pakistan Journal of Medical Sciences, Vol. 37, no. 4, May 2021, doi:10.12669/pjms.37.4.4057.