Zerner80

M. C. Zerner, G. H. Lowe, R. F. Kirchner, and U. T. Mueller-Westerhoff, “An Intermediate Neglect of Differential Overlap Technique for Spectroscopy of Transition-Metal Complexes. Ferrocene,” J. Am. Chem. Soc., 102 (1980) 589-99. DOI: 10.1021/ja00522a025