1. Adams, D.J.: 1981, “Cosmic X-ray Astronomy”, Heyden & Son Inc., London.
2. Appenzeller, I., Lequeux, J., Silk, J.: 1980, “Star Formation”, 10th Advanced Course, Swiss Society of Astronomy and Astrophysics, Saas-Fee, Geneva Observatory.
3. Dyson, J.E., Williams, D.A.: 1980, “The Physics of the Interstellar Medium”, Manchester University Press.
4. Dolginov, A.Z., Gnedin, Yu. N., Silant’ev, N.A.: 1979, “Propagation and Polarization of Radiation through Cosmic Medium”, Nauka, Moscow. (In Russian)
5. Kaplan, S.A., Pikel’ner, S.B.: 1979, “Physics of the Interstellar Medium”, ed. N.G. Bochkarev, Nauka, Moscow. ( In Russian )