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2. H. James and A., Coolidge, J. Chem. Phys. 1, 825 (1933).
3. W. Kolos and L., Wolniewicz, J. Chem. Phys. 43, 2429 (1965).
4. H. F. Schaefer III, “The Electronic Structure of Atoms and Molecules” Academic Press, New York 1972.
5. See, for example, “IBMOL-5 Program User’s Guide,” E. Clementi and J. Mehl, IBM Research Report RJ 889, 1971 (unpublished) and “BISON, Part I, User’s Manual and General Program Description,” A. C. Wahl, P. J. Bertoncini, K. Kaiser, and R. M. Land, Argonne National Laboratory Research Report ANL-7271, 1968 (unpublished).