Clayton, Geoffrey C. (1996). “The R Coronae Borealis Stars”. Publications of the Astronomical Society of the Pacific108: 225. doi:10.1086/133715. ISSN0004-6280.
Hema, B. P.; Pandey, Gajendra; Lambert, David L. (2012). “THE GALACTIC R CORONAE BOREALIS STARS: THE C2SWAN BANDS, THE CARBON PROBLEM, AND THE12C/13C RATIO”. The Astrophysical Journal747 (2): 102. doi:10.1088/0004-637X/747/2/102. ISSN0004-637X.
Clayton, Geoffrey C. (1996). “The R Coronae Borealis Stars”. Publications of the Astronomical Society of the Pacific108: 225. doi:10.1086/133715. ISSN0004-6280.
Hema, B. P.; Pandey, Gajendra; Lambert, David L. (2012). “THE GALACTIC R CORONAE BOREALIS STARS: THE C2SWAN BANDS, THE CARBON PROBLEM, AND THE12C/13C RATIO”. The Astrophysical Journal747 (2): 102. doi:10.1088/0004-637X/747/2/102. ISSN0004-637X.