1. J. C. Mermilliod, Astron. Astrophys. 109, 48 (1982).
2. J. Fabregat and J. M. Torrejón, Astron. Astrophys. 375, 451 (2000).
3. D. R. Gies, IAU Coll. 175, The Be Phenomenon in Early Type Stars, M. A. Smith, H. F. Henrichs, and J. Fabregat, eds., PASP Conf. Ser V. 214, p. 668 (2000).
4. M. J. Coe, IAU Coll. 175, The Be Phenomenon in Early Type Stars, M. A. Smith, H. F. Henrichs, and J. Fabregat, eds., PASP Conf. Ser V. 214, p. 656 (2000).
5. Z. Balog and S. Kenyon, Astron. J. 124, 2083 (2002).