1. V. I. Sokolov and N. A. Fedorovich, Phys. Status Solidi A 99, 151 (1987).
2. F. Maurice, L. Meny, and R. Tixier, Microanalysis and Scanning Electron Microscopy (Les Éditions de Physique, 1978), p. 527.
3. M. V. Zamoryanskaya, A. N. Zamoryanskii, and I. A. Vainshenker, Prib. Tekh. Éksp. No. 4, 161 (1987).
4. A. R. Silin’ and A. N. Trukhin, Point Defects and Elementary Excitations in Crystalline and Glassy SiO2 [in Russian] (Riga, Zinatne, 1985), 243 pp.
5. A. N. Trukhin and A. É. Plaudis, Fiz. Tverd. Tela (Leningrad) 21, 1109 (1979) [Sov. Phys. Solid State 21, 644 (1979)].