Apichatbutr Y. Physiologic and Other Effects of Silicone Mask Respirator N99 in the Coronavirus 2019 Outbreaks. Vajira Med J [internet]. 2021 Feb. 24 [cited 2026 Sep. 19];65(1):1-12. available from: https://he02.tci-thaijo.org/index.php/VMED/article/view/246793