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\bibitem{Hartogh_etal2010} Hartogh, P., Jarchow, C., Lellouch, E., de Val-Borro, M., Rengel, M., Moreno, R., et al. (2010). Herschel/HIFI observations of Mars: First detection of O$_{2}$ at submillimetre wavelengths and upper limits on HCl and H$_{2}$O$_{2}$. \textit{Astron. Astrophys.}, \textit{521}, L49.

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