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\bibitem{Tian_etal2011} {\textquotedblleft}\textit{Nanodiamonds do not provide unique evidence for a Younger Dryas impact}{\textquotedblright}. Tian H, Schryvers D, Claeys P, Proceedings of the National Academy of Sciences of the United States of America \textbf{108}, 40 (2011).   http://doi.org/10.1073/pnas.1007695108

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