Klebesadel, Ray W; Strong, Ian B; Olson, Roy A (1973). "Observations of Gamma-Ray Bursts of Cosmic Origin". The Astrophysical Journal. 182: L85. Bibcode:1973ApJ...182L..85K. doi:10.1086/181225.
Bonnell, J. T.; Klebesadel, R. W. (1996). "A brief history of the discovery of cosmic gamma-ray bursts". AIP Conference Proceedings. 384: 979. Bibcode:1996AIPC..384..977B. doi:10.1063/1.51630.
Conner JP, Evans WD, Belian RD (1969). "The Recent Appearance of a New X-Ray Source in the Southern Sky". The Astrophysical Journal. 157: L157–159. Bibcode:1969ApJ...157L.157C. doi:10.1086/180409.
Belian RD, Conner JP, Evans WD (1972). "A Probable Precursor to the X-Ray Nova Centaurus XR-4". The Astrophysical Journal. 171: L87–90. Bibcode:1972ApJ...171L..87B. doi:10.1086/180874.
Klebesadel, Ray W; Strong, Ian B; Olson, Roy A (1973). "Observations of Gamma-Ray Bursts of Cosmic Origin". The Astrophysical Journal. 182: L85. Bibcode:1973ApJ...182L..85K. doi:10.1086/181225.
Bonnell, J. T.; Klebesadel, R. W. (1996). "A brief history of the discovery of cosmic gamma-ray bursts". AIP Conference Proceedings. 384: 979. Bibcode:1996AIPC..384..977B. doi:10.1063/1.51630.
Conner JP, Evans WD, Belian RD (1969). "The Recent Appearance of a New X-Ray Source in the Southern Sky". The Astrophysical Journal. 157: L157–159. Bibcode:1969ApJ...157L.157C. doi:10.1086/180409.
Belian RD, Conner JP, Evans WD (1972). "A Probable Precursor to the X-Ray Nova Centaurus XR-4". The Astrophysical Journal. 171: L87–90. Bibcode:1972ApJ...171L..87B. doi:10.1086/180874.
Dunning, Brian. "Skeptoid #190: The Bell Island Boom". Skeptoid. Retrieved June 19, 2017. quote (emphasis added): "They also picked up large lightning flashes, and it was in part from the Vela satellites that we learned about lightning superbolts. About five of every ten million bolts of lightning is classified as a superbolt, which is just what it sounds like: An unusually large bolt of lightning, lasting an unusually long time: About a thousandth of a second. Superbolts are almost always in the upper atmosphere, and usually over the oceans."