Justtanont, K., Decin, L., Schöier, F. L., Maercker, M., Olofsson, H., Bujarrabal, V., et al. (2010). A HIFI preview of warm molecular gas around Ï‡ Cygni: first detection of H2O emission toward an S-type AGB star. Astron. Astrophys., 521, L6.