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\bibitem{Ro_etal2002} {\textquotedblleft}\textit{Single-particle characterization of urban aerosol particles collected in three Korean cities using low-Z electron probe x-ray microanalysis}{\textquotedblright}. Ro C-U, Kim H, Oh K-Y, Yea SK, Lee CB, Jang M, Van Grieken R, Environmental science and technology \textbf{36}, 4770 (2002).   http://doi.org/10.1021/ES025697Y

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