Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
Mason, Brian D.; et al. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog", The Astronomical Journal, 122 (6), U. S. Naval Observatory, Washington D.C.: 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.
Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
Pizzolato, N.; Maggio, A.; Sciortino, S. (September 2000), "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases", Astronomy and Astrophysics, 361: 614–628, Bibcode:2000A&A...361..614P
Mason, Brian D.; et al. (December 2001), "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog", The Astronomical Journal, 122 (6), U. S. Naval Observatory, Washington D.C.: 3466–3471, Bibcode:2001AJ....122.3466M, doi:10.1086/323920.