Kaluzienski, L. J.; Holt, S. S.; Boldt, E. A.. Evidence for a 16.6 day period from Circinus X-1. Astrophysical Journal, 1976, s. L71–L75. DOI: 10.1086/182235.
S. Heinz; P. Sell; R.P. Fender. The Youngest Known X-ray Binary: Circinus X-1 and its Natal Supernova Remnant. The Astrophysical Journal, December 2013, s. 171. DOI: 10.1088/0004-637X/779/2/171.