1969, J. Chem. Phys., 51, 2657, 10.1063/1.1672392
1971, J. Chem. Phys., 54, 724, 10.1063/1.1674902
1972, J. Chem. Phys., 56, 2257, 10.1063/1.1677527
1973, Theor. Chim. Acta, 28, 213, 10.1007/BF00533485
1934, Phys. Rev., 46, 618, 10.1103/PhysRev.46.618
1975, Int. J. Quantum Chem., 9, 229, 10.1002/qua.560090204
1976, Int. J. Quantum Chem. Symp., 10, 1, 10.1002/qua.560100102
1978, Int. J. Quantum Chem., 14, 91, 10.1002/qua.560140109