Penny, Laura R.; Seyle, Debra; Gies, Douglas R.; Harvin, James A.; Bagnuolo, Jr.; Thaller, M. L.; Fullerton, A. W.; Kaper, L. Tomographic Separation of Composite Spectra. VII. The Physical Properties of the Massive Triple System HD 135240 (Delta Circini). The Astrophysical Journal. 2001, 548 (2): 889–99. Bibcode:2001ApJ...548..889P. doi:10.1086/319031.
Evans, Nancy Remage; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.; Karovska, Margarita; Tingle, Evan. Binary Cepheids: Separations and Mass Ratios in 5M ⊙ Binaries. Astronomical Journal. 2013, 146 (4): 93, 10 pp. Bibcode:2013AJ....146...93R. arXiv:1307.7123v1. doi:10.1088/0004-6256/146/4/93.
Greeley, Bradford W.; Blair, William P.; Long, Knox S. Hopkins Ultraviolet Telescope Observations of Nova Circini 1995 and Nova Aquilae 1995. Astrophysical Journal Letters. 1995, 454: L43–46. Bibcode:1995ApJ...454L..43G. doi:10.1086/309767.
Penny, Laura R.; Seyle, Debra; Gies, Douglas R.; Harvin, James A.; Bagnuolo, Jr.; Thaller, M. L.; Fullerton, A. W.; Kaper, L. Tomographic Separation of Composite Spectra. VII. The Physical Properties of the Massive Triple System HD 135240 (Delta Circini). The Astrophysical Journal. 2001, 548 (2): 889–99. Bibcode:2001ApJ...548..889P. doi:10.1086/319031.
Evans, Nancy Remage; Bond, Howard E.; Schaefer, Gail H.; Mason, Brian D.; Karovska, Margarita; Tingle, Evan. Binary Cepheids: Separations and Mass Ratios in 5M ⊙ Binaries. Astronomical Journal. 2013, 146 (4): 93, 10 pp. Bibcode:2013AJ....146...93R. arXiv:1307.7123v1. doi:10.1088/0004-6256/146/4/93.
Greeley, Bradford W.; Blair, William P.; Long, Knox S. Hopkins Ultraviolet Telescope Observations of Nova Circini 1995 and Nova Aquilae 1995. Astrophysical Journal Letters. 1995, 454: L43–46. Bibcode:1995ApJ...454L..43G. doi:10.1086/309767.
Cannon, A.J. Becker's Nova Circini No. 2 1926. Harvard College Observatory Bulletin. 1930, 872 (872): 1–2. Bibcode:1930BHarO.872....1C.