Bahli, Zahid Mehmood. “DOES EVIDENCE BASED MEDICINE SUPPORT THE EFFECTIVENESS OF SURGICAL FACEMASKS IN PREVENTING POSTOPERATIVE WOUND INFECTIONS IN ELECTIVE SURGERY?”. Journal of Ayub Medical College Abbottabad, vol. 21, no. 2, June 2009, pp. 166-70, https://jamc.ayubmed.edu.pk/index.php/jamc/article/view/3652.