1. R.S. Knox, Theory of Excitons, Solid State Physics, Suppl.5; F. Seitz and D. Turnbull eds, Academic Press, New York (1963).
2. Excitons, K. Cho ed, Topics in Current Physics 14, Springer, Berlin (1979).
3. Excitons, E.I. Rashba and M.D. Sturge eds., Modern Problems in Condensed Matter Sciences 2, North Holland, Amsterdam (1982).
4. B. Hönerlage, R. Lévy, J.B. Grun, C. Klingshirn and K. Bohnert, Physics Reports 124, 161 (1985).
5. H. Haug and S.W. Koch, Quantum Theory of Optical and Electronic Properties of Semiconductors, World Scientific, Singapore (1990).