1. C. Ashman, S. N. Khanna, and M. R. Pederson, Phys. Stat. Sol. (b), No. 217, 323 (2000).
2. R. V. Vedrinskii and I. I. Geguzin, X-Ray Absorption Spectra of Solids [in Russian], Energoatomizdat, Moscow (1991).
3. J. P. K. Doye and D. J. Wales, Phys. Rev. B, 59, No. 3, 2292 (1999).
4. C. M. Teodorescu, J. M. Esteva, M. Womes, et al., J. Electron Spectr. Related Phenom., No. 106, 233 (2000).
5. D. Zhang and R. G. Cooks, Int. J. Mass Spectr., Nos. 195/196, 667 (2000).