WR 20a

References

1. Rauw2004
   Rauw, G., De Becker, M., Naze, Y., Crowther, P. A., Gosset, E., Sana, H., van der Hucht, K. A., Vreux, J.-M., & Williams, P. M. “WR 20a: A Massive Cornerstone Binary System Comprising Two Extreme Early-type Stars”: 2004, Astronomy & Astrophysics, Volume 420, pp. L9-L13
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004A%26A...420L...9R&db_key=AST&high=3f2ea4260a01220

2. Bonanos2004
   Bonanos, A. Z., Stanek, K. Z., Udalski, A., Wyrzykowski, L., Zebrun, K., Kubiak, M., Szymanski, M. K., Szewczyk, O., Pietrzynski, G. & Soszynski, I. “WR 20a Is An Eclipsing Binary: Accurate Determination of Parameters for an Extremely Massive Wolf-Rayet System”: 2004, The Astrophysical Journal, Volume 611, pp. L33-L36
   http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2004ApJ...611L..33B&db_key=AST&high=3f2ea4260a00592