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\bibitem{Smekens_etal2007} {\textquotedblleft}\textit{Characterization of individual soot aggregates from different sources using image analysis}{\textquotedblright}. Smekens A, Godoi RHM, Vervoort M, van Espen P, Potgieter-Vermaak SS, Van Grieken R, Journal of atmospheric chemistry \textbf{56}, 211 (2007).   http://doi.org/10.1007/S10874-006-9050-X

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