1. Foresman, J. B.; Frisch, ®. Exploring Chemistry with Electronic Structure Methods; Gaussian: Pittsburgh, PA, 1996.
2. Hehre, W. J.; Shusterman, A. J.; Nelson, J. E. The Molecular Modeling Workbook for Organic Chemistry; Wavefunction Inc.: Irvine, CA, 1998.
3. Atkins, P. Physical Chemistry, 6th ed.; W. H. Freeman & Co., New York, 1998.