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\bibitem{Loenen_etal2010} Loenen, A. F., van der Werf, P. P., G{\"u}sten, R., Meijerink, R., Israel, F. P., Requena-Torres, M. A., et al. (2010). Excitation of the molecular gas in the nuclear region of M~82. \textit{Astron. Astrophys.}, \textit{521}, L2.

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