1. See, for reviews, J. R. Chelikowsky and M. L. Cohen, Electronic Structure and Optical Properties of Semiconductors, 2nd Ed., (Springer Verlag, Heidelberg, 1989) and the article by J. R. Chelikowsky in this Volume.
2. M. T. Yin and M. L. Cohen, Phys. Rev. Lett. 45, 1004 (1980)
3. M. T. Yin and M. L. Cohen, Phys. Rev. B26, 3259 (1982)
4. M. T. Yin and M. L. Cohen, Phys. Rev. B26, 5668 (1982).
5. For a review see S. G. Louie, in: Electronic Structure, Dynamics and Quantum Structural Properties of Condensed Matter, eds. J. Devreese and P. Van Camp (Plenum, New York, 1985), p. 335, and references therein.