1. A new method for large-scale Cl calculations
2. Siegbahn, P. E. M. 1975.Proceedings of SRC Atlas Symposium Number 4, Quantum Chemistry: The State of the ArtEdited by: Saunders, V. R. and Brown, J. 81Rutherford Laboratory, Chilton, Didcot, Oxfordshire. Pakiari, A. H., and Handy, N. C., 1975,Theor. chim. Acta40, 17. Roos, B. O., and Siegbahn, P. E. M., 1977,Modern Theoretical Chemistry, Vol. 3, edited by H. F. Schaefer (Plenum), Chap. 7. Roos, B. O., and Siegbahn, P. E. M., 1977,J. Am. chem. Soc.99, 7716. Lucchese, R. R., and Schaefer, H. F., 1978,J. chem. Phys.68, 769. Roos, B. O., and Siegbahn, P. E. M., 1979,J. chem. Phys.70, 5391. Handy, N. C., Goddard, J. D., and Schaefer, H. F., 1979,J. chem. Phys.71, 426. Roos, B. O., and Siegbahn, P. E. M., 1980,Int. J. quant. Chem.17, 485
3. Generalizations of the direct CI method based on the graphical unitary group approach. II. Single and double replacements from any set of reference configurations
4. Theory of self‐consistent electron pairs. An iterative method for correlated many‐electron wavefunctions
5. Direct determination of pair natural orbitals