B. Binggeli; A. Sandage; G. A. Tammann (1985). «Studies of the Virgo Cluster. II - A catalog of 2096 galaxies in the Virgo Cluster area. V - Luminosity functions of Virgo Cluster galaxies». The Astronomical Journal. 90: 1681–1759. Bibcode:1985AJ.....90.1681B. doi:10.1086/113874.
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B. Binggeli; A. Sandage; G. A. Tammann (1985). «Studies of the Virgo Cluster. II - A catalog of 2096 galaxies in the Virgo Cluster area. V - Luminosity functions of Virgo Cluster galaxies». The Astronomical Journal. 90: 1681–1759. Bibcode:1985AJ.....90.1681B. doi:10.1086/113874.