Crook, Aidan C. και άλλοι. (February 2007). «Groups of Galaxies in the Two Micron All Sky Redshift Survey». The Astrophysical Journal655 (2): 790–813. doi:10.1086/510201. Bibcode: 2007ApJ...655..790C.
Crook, Aidan C. και άλλοι. (February 2007). «Groups of Galaxies in the Two Micron All Sky Redshift Survey». The Astrophysical Journal655 (2): 790–813. doi:10.1086/510201. Bibcode: 2007ApJ...655..790C.