Chavez-Ruiz, Manuel, Lenin Rueda-Torres, Betsabé Ruffner-Camargo, and Cristofer Bellido-Achahui. “Methodology for Evaluating the Level of Respiratory Protection of Masks and Respirators Against Particles Similar to Those That Transmit SARS-CoV-2”. Revista Peruana de Medicina Experimental y Salud Pública 38, no. 3 (September 30, 2021): 391–8. Accessed June 23, 2024. https://rpmesp.ins.gob.pe/index.php/rpmesp/article/view/8036.