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\bibitem{Ravindra_etal2008} {\textquotedblleft}\textit{Variation in particulate PAHs levels and their relation with the transboundary movement of the air masses}{\textquotedblright}. Ravindra K, Wauters E, Van Grieken R, The science of the total environment \textbf{396}, 100 (2008).   http://doi.org/10.1016/J.SCITOTENV.2008.02.018

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