Kelkar, Uday Siddharaj, Bageshri Gogate, Satish Kurpad, Parikshit Gogate, and Madan Deshpande. 2013. “How Effective Are Face Masks in Operation Theatre? A Time Frame Analysis and Recommendations”. International Journal of Infection Control 9 (1). https://doi.org/10.3396/ijic.v9i1.10788.