1. Reed, M., Simon, B.: Methods of modern mathematical physics. II. New York: Academic Press 1975
2. Englisch, H.: One-dimensional Schr�dinger operators with ergodic potential. Z. Anal. Anw.2, 411?426 (1983)
3. Pastur, L.A.: Spectra of random self-adjoint operators. Usp. Mat. Nauk.28, 3?64 (1973)
4. Kirsch, W., Martinelli, F.: On the density of states of Schr�dinger operators with a random potential. J. Phys. A15, 2139?2156 (1982)
5. Englisch, H.: The phase formalism for one-dimensional Schr�dinger operators with a random potential. Preprint ICTP Trieste, to appear in Rept. Math. Phys.