1. see for example: Narrow-band phenomena. Influence of electrons with both band and localized character. Fuggle, J.C., Sawatzky, G.A., Allen, J.W. (eds.). New York: Plenum Press 1988
2. Hohenberg, P., Kohn, W.: Phys. Rev. A140, 1133 (1964)
3. Kohn, W., Sham, L.J.: Phys. Rev. B136, 864 (1965)
4. Brooks, M.S.S., Nordström, L., Johansson, B.: J. Phys.3, 3393 (1991)
5. Eriksson, O., Johansson, B., Brooks, M.S.S., Skriver, H.L.: Phys. Rev. B40, 9508 (1989)