Lead
S.J.A van Gisbergen, J.G. Snijders, and E.J. Baerends, J. Chem. Phys. 103, 9347 (1995)
Suggested
V.P. Osinga, S.J.A van Gisbergen, J.G. Snijders, and E.J. Baerends, J. Chem. Phys 106, 5091 (1997)
