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\bibitem{Mao_etal2009} {\textquotedblleft}\textit{Estimation of ecotoxicity of petroleum hydrocarbon mixtures in soil based on HPLC-GCXGC analysis}{\textquotedblright}. Mao D, Lookman R, van de Weghe H, Weltens R, Vanermen G, Brucker N, Diels L, Chemosphere \textbf{77}, 1508 (2009).   http://doi.org/10.1016/J.CHEMOSPHERE.2009.10.004

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