1. V. L. Afanasiev and A. V. Moiseev, Astronomy Letters 31 (3), 194 (2005).
2. A. A. Batrakov, A. F. Kholtygin, S. Fabrika, and A. Valeev, ASP Conf. Ser. 518, 153 (2019).
3. A. A. Batrakov, A. F. Kholtygin, and S. Hubrig, in Stars and their variability observed from space, Proc. Int. Conf. held in Vienna, Austria, August 19–23, 2019, pp. 163–164 (2020).
4. E. F. Borra and J. D. Landstreet, Astrophys. J.185, L139 (1973).
5. G. A. Chountonov, in Spectroscopic methods in modern astrophysics, ed. by L. Mashonkina and M. Sachkov, Proc. Conf. held in Moscow, Russia, September 13–15, 2006, pp. 336–349 (2007).