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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. arXiv:0708.0570. doi:10.1086/521990.
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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. arXiv:0708.0570. doi:10.1086/521990.