Kellogg, E.; Tananbaum, H.; Harnden, F. R., Jr.; Gursky, H.; Giacconi, R.; Grindlay, J. (August 1973). "The X-ray Structure of the Vela X Region Observed from Uhuru". The Astrophysical Journal. 183: 935–940. Bibcode:1973ApJ...183..935K. doi:10.1086/152279.
Kellogg, E.; Tananbaum, H.; Harnden, F. R., Jr.; Gursky, H.; Giacconi, R.; Grindlay, J. (August 1973). "The X-ray Structure of the Vela X Region Observed from Uhuru". The Astrophysical Journal. 183: 935–940. Bibcode:1973ApJ...183..935K. doi:10.1086/152279.