Lelieveld J, Helleis F, Borrmann S, Cheng Y, Drewnick F, Haug G, Klimach T, Sciare J, Su H, Pöschl U. Model Calculations of Aerosol Transmission and Infection Risk of COVID-19 in Indoor Environments. International Journal of Environmental Research and Public Health. 2020; 17(21):8114. (2020-11-03). https://doi.org/10.3390/ijerph17218114