Nicholas J. McConnell et al.. Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies. „Nature”. 480, s. 215-218, 2011-12-08. DOI: 10.1038/nature10636. arXiv:1112.1078. (ang.).
Courtney Seligman: NGC 3842. [w:] Celestial Atlas [on-line]. [dostęp 2014-07-14]. (ang.).
doi.org
Nicholas J. McConnell et al.. Two ten-billion-solar-mass black holes at the centres of giant elliptical galaxies. „Nature”. 480, s. 215-218, 2011-12-08. DOI: 10.1038/nature10636. arXiv:1112.1078. (ang.).