Ibata, R.; Bellazzini, M.; Chapman, S. C.; Dalessandro, E.; Ferraro, F.; Irwin, M.; Lanzoni, B.; Lewis, G. F.; Mackey, A. D. (2009). Density and Kinematic Cusps in M54 at the Heart of the Sagittarius Dwarf Galaxy: Evidence for a 104 Black Hole?. Astrophysical Journal Letters. 699 (2): L169-L173. arXiv:0906.4894. doi:10.1088/0004-637X/699/2/L169.
doi.org
Geisler, Doug; Wallerstein, George; Smith, Verne V.; Casetti-Dinescu, Dana I. (2007). Chemical Abundances and Kinematics in Globular Clusters and Local Group Dwarf Galaxies and Their Implications for Formation Theories of the Galactic Halo. Publications of the Astronomical Society of the Pacific. 119 (859): 939—961. Bibcode:2007PASP..119..939G. doi:10.1086/521990.
Siegel, Michael H.; Dotter, Aaron; Majewski, Steven R.; Sarajedini, Ata; Chaboyer, Brian; Nidever, David L.; Anderson, Jay; Marín-Franch, Antonio; Rosenberg, Alfred (2007). The ACS Survey of Galactic Globular Clusters: M54 and Young Populations in the Sagittarius Dwarf Spheroidal Galaxy. Astrophysical Journal Letters. 667 (1): L57-L60. Bibcode:2007ApJ...667L..57S. doi:10.1086/522003.
Ibata, R.; Bellazzini, M.; Chapman, S. C.; Dalessandro, E.; Ferraro, F.; Irwin, M.; Lanzoni, B.; Lewis, G. F.; Mackey, A. D. (2009). Density and Kinematic Cusps in M54 at the Heart of the Sagittarius Dwarf Galaxy: Evidence for a 104 Black Hole?. Astrophysical Journal Letters. 699 (2): L169-L173. arXiv:0906.4894. doi:10.1088/0004-637X/699/2/L169.
harvard.edu
ui.adsabs.harvard.edu
Geisler, Doug; Wallerstein, George; Smith, Verne V.; Casetti-Dinescu, Dana I. (2007). Chemical Abundances and Kinematics in Globular Clusters and Local Group Dwarf Galaxies and Their Implications for Formation Theories of the Galactic Halo. Publications of the Astronomical Society of the Pacific. 119 (859): 939—961. Bibcode:2007PASP..119..939G. doi:10.1086/521990.
Siegel, Michael H.; Dotter, Aaron; Majewski, Steven R.; Sarajedini, Ata; Chaboyer, Brian; Nidever, David L.; Anderson, Jay; Marín-Franch, Antonio; Rosenberg, Alfred (2007). The ACS Survey of Galactic Globular Clusters: M54 and Young Populations in the Sagittarius Dwarf Spheroidal Galaxy. Astrophysical Journal Letters. 667 (1): L57-L60. Bibcode:2007ApJ...667L..57S. doi:10.1086/522003.