1. Fock M. V., Alentzev M. N.: Zh. Prikl. Spektrosk.11 (1969) 926; Trudy FIAN59 (1972) 3.
2. Pastrňák J.: Czech. J. Phys. B37 (1987) 942.
3. Demidovich B. P., Maron J. A.: Computational Mathematics. Mir publishers, Moscow, 1981, p. 469.
4. James F., Roos M.: Comput. Phys. Commun.10 (1975) 343.
5. Forsythe G. E., Malcolm M.A., Molez C. B.: Computer Methods for Mathematical Computations. Prentice-Hall, Englewoo. Cldiffs (N. J.), 1975, p. 48.