Irwin, M. J.; Demers, Serge; Kunkel, W. E. (1995). „The PYXIS Cluster: A Newly Identified Galactic Globular Cluster”. Astrophysical Journal Letters. 453: L21. Bibcode:1995ApJ...453L..21I. doi:10.1086/513301.
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Irwin, M. J.; Demers, Serge; Kunkel, W. E. (1995). „The PYXIS Cluster: A Newly Identified Galactic Globular Cluster”. Astrophysical Journal Letters. 453: L21. Bibcode:1995ApJ...453L..21I. doi:10.1086/513301.