SPARKE, L. S.; GALLAGHER, J. S. Galaxies in the Universe: An Introduction. Cambridge: Cambridge University Press, 2007. Dostupné online. ISBN978-0-521-67186-6. S. 244. (anglicky)
MARSCHER, Alan P.; JORSTAD, Svetlana G.; D'ARCANGELO, Francesca D., et al. The inner jet of an active galactic nucleus as revealed by a radio-to-γ-ray outburst. S. 966–969. Nature [online]. Duben 2008 [cit. 2018-11-26]. Roč. 7190, s. 966–969. Dostupné online. doi:10.1038/nature06895. Bibcode2008Natur.452..966M. (anglicky)
MARSCHER, Alan P.; JORSTAD, Svetlana G.; D'ARCANGELO, Francesca D., et al. The inner jet of an active galactic nucleus as revealed by a radio-to-γ-ray outburst. S. 966–969. Nature [online]. Duben 2008 [cit. 2018-11-26]. Roč. 7190, s. 966–969. Dostupné online. doi:10.1038/nature06895. Bibcode2008Natur.452..966M. (anglicky)
OVERBYE, Dennis. It Came From a Black Hole, and Landed in Antarctica. New York Times [online]. 2018-07-12 [cit. 2018-11-26]. Dostupné online. (anglicky)