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\bibitem{Smets_etal2016} {\textquotedblleft}\textit{Airborne bacteria in the atmosphere : presence, purpose, and potential}{\textquotedblright}. Smets W, Moretti S, Denys S, Lebeer S, Atmospheric environment : an international journal \textbf{139}, 214 (2016).   http://doi.org/10.1016/J.ATMOSENV.2016.05.038

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