V. G. Zakrzewski, J. V. Ortiz, J. A. Nichols, D. Heryadi, D. L. Yeager, and J. T. Golab, “Comparison of perturbative and multiconfigurational electron propagator methods,” Int. J. Quant. Chem., 60 (1996) 29-36. DOI: 3.0.CO;2-7>10.1002/(SICI)1097-461X(1996)60:13.0.CO;2-7