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\bibitem{Flynn_etal2006} {\textquotedblleft}\textit{Elemental compositions of comet 81P/Wild 2 samples collected by Stardust}{\textquotedblright}. Flynn GJ, Janssens K, Vekemans B, [et al], Science \textbf{314}, 1731 (2006).   http://doi.org/10.1126/SCIENCE.1136141

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