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\bibitem{Ro_etal2001} {\textquotedblleft}\textit{Single-particle analysis of aerosols at Cheju Island, Korea, using low-Z electron probe X-ray microanalysis: a direct proof of nitrate formation from sea salts}{\textquotedblright}. Ro C-U, Oh K-Y, Kim H, Kim YP, Lee CB, Kim K-H, Kang CH, Os{\'a}n J, de Hoog J, Worobiec A, Van Grieken R, Environmental science and technology \textbf{35}, 4487 (2001).   http://doi.org/10.1021/ES0155231

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