“COVID-19 – The Efficacy of the LEAF-Mask Measured by Assessing the Viral Load of the mask’s Inner and Outer Surface Used by Nurses in ICUs Compared to the N95: A Phase II, Multicenter, Randomized, Controlled, Open-Label, Clinical Trial Protocol”. Principles and Practice of Clinical Research 7, no. 1 (March 30, 2021). Accessed November 23, 2024. https://journal.ppcr.org/index.php/ppcrjournal/article/view/128.