1. L. P. Kudrin and M. Ya. Mazeev, Atomnaya Énergiya,22, 83 (1966).
2. P. Gombash, Statistical Theory of the Atom [Russian translation], Moscow, IL (1951).
3. Froese. Proc. Cambridge Phys. Soc.,53, 206 (1957).
4. D. Hartree and W. Hartree, Proc. Roy. Soc.,164, 167 (1938).
5. D. Hartree, Calculations of Atomic Structures [Russian translation], Moscow, IL (1960).