1. A. Peres: inQuantum Measurements and Chaos, edited byE. R. Pike andS. Sarkar (Plenum, New York, N.Y., 1987).
2. B. V. Chirikov, F. M. Izrailev andL. Shepelyansky:Sov. Sci., Rev. C,2, 209 (1981).
3. E. Nelson:Phys. Rev.,150, 1079 (1966).
4. B. Misra, I. Prigogine andM. Courbage:Proc. Nat. Acad. Sci. USA,76, 4768 (1979).
5. G. Grössing:Phys. Lett. A,118, 381 (1986).