1. J. C. Slater, Self-consistent Field Methods for Molecules and Solids [Russian translation], Mir, Moscow (1978).
2. G. M. Zhidomirov and L. I. Yastrebov, in: Methods of Quantum Chemistry [in Russian], Chernogolovka (1979), p. 81.
3. R. P. Messmer, The Nature of Surface Chemical Bonds, North-Holland, Amsterdam (1979), p. 51.
4. V. A. Fock, Principles of Quantum Mechanics [in Russian], Nauka, Moscow (1976).
5. H. A. Bethe, Quantum Mechanics [Russian translation], Mir, Moscow (1965).