Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. (2008). “Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters”. Astronomy and Astrophysics481 (3): 777–97. arXiv:0801.4289. Bibcode: 2008A&A...481..777S. doi:10.1051/0004-6361:20077125.
Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. (2008). “Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters”. Astronomy and Astrophysics481 (3): 777–97. arXiv:0801.4289. Bibcode: 2008A&A...481..777S. doi:10.1051/0004-6361:20077125.
Searle, S. C.; Prinja, R. K.; Massa, D.; Ryans, R. (2008). “Quantitative studies of the optical and UV spectra of Galactic early B supergiants. I. Fundamental parameters”. Astronomy and Astrophysics481 (3): 777–97. arXiv:0801.4289. Bibcode: 2008A&A...481..777S. doi:10.1051/0004-6361:20077125.