Facemasks in the COVID-19 era: A health hypothesishttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC7680614/ 2021 Jan; 146: 110411. Published online 2020 Nov 22. doi: 10.1016/j.mehy.2020.110411 PMCID: PMC7680614 PMID: 33303303 Facemasks in the COVID-19 er
