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\bibitem{Ravindra_etal2006} {\textquotedblleft}\textit{Seasonal and site-specific variation in vapour and aerosol phase PAHs over Flanders (Belgium) and their relation with anthropogenic activities}{\textquotedblright}. Ravindra K, Bencs L, Wauters E, de Hoog J, Deutsch F, Roekens E, Bleux N, Berghmans P, Van Grieken R, Atmospheric environment : an international journal \textbf{40}, 771 (2006).   http://doi.org/10.1016/J.ATMOSENV.2005.10.011

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