1. O. G. Badalyan, in Activity Cycles on the Sun and Stars, Proceedings of the Workshop, Dec. 18–19, 2009, Moscow, Ed. by V. N. Obridko and Yu. A. Nagovitsyn (BBM, St.-Peterburg, 2009a), p. 205.
2. O. G. Badalyan, Astron. Rep. 53, 262 (2009b).
3. O. G. Badalyan, New Astron. 15, 135 (2010).
4. O. G. Badalyan, Astron. Zh. 86, 1008 (2011).
5. O. G. Badalyan and V. N. Obridko, New Astron. 16, 357 (2011).