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\bibitem{Melnick_etal2010} Melnick, G. J., Tolls, V., Neufeld, D. A., Bergin, E. A., Phillips, T. G., Wang, S., et al. (2010). Herschel observations of EXtra-Ordinary Sources (HEXOS): Observations of H$_{2}$O and its isotopologues towards Orion KL. \textit{Astron. Astrophys.}, \textit{521}, L27.

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