1. 1. I.V.Myntianskyi, I.I.Grygorchak, Z.D.Kovaliuk, Solid State Phys., 28, 1263 (1986).
2. 2. I.I.Grygorchak, Phys. Chem. Sol. State. 88, 3 (2002).
3. in: Proc. of the Acad. Sci. Soviet Union;Kozmyk;Inorg Mater,1987
4. 4. I.I.Grygorchak, in: Material Science of Low Energy Gap and Layered Semiconductors, Naukova Dumka, Kiev (1989) [in Russian].
5. Electronic structure of low-pressure and high-pressure phases of silicon disulfide