1. Harriss,D.K., Mitchell,C.W., Musulin, B.: Theoret. chim. Acta (Berl.) 1, 93 (1963).
2. Weinbaum,S.: J. chem. Physics 1, 593 (1933).
3. Slater,J.C.: Physic. Rev. 36, 57 (1930).
4. Mulliken,R.S.: J. Chim. physique 46, 500 (1949).
5. Herzberg,G.: Molecular spectra and molecular structure, I. Spectra of diatomic molecules, New York: D. Van Nostrand Co., Inc. 1950.