1. Baliunas, S.L. and Vaughan, A.H.: 1985, Ann. Rev. Astron Astrophys. 23, 379
2. Baliunas, S.L.: 1986, in Cool Stars, Stellar Systems and the Sun, M.Zeilik and D.Gibson eds., Springer, Berlin, p. 3
3. Baliunas, S.L.: 1986, in Cool Stars, Stellar Systems and the Sun, M.Zeilik and D.Gibson eds., Springer, Berlin, p. 3
4. Belvedere, G.: 1985, Solar Phys. 100, 363
5. Belvedere, G.: 1985, Solar Phys. 100, 363