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National Library of Medicine:
* 2005 ((https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2569983/ Public Health Strategy and the Police Powers of the State))
* 2009 ((https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2662657/ Face Mask Use and Control of Respiratory Virus Transmission in Households))
Vgl.: {{include page="/Comment23" nomark=1}}