1. F. Bloch, Phys. Rev. 102, 104 (1956); Phys. Rev. 105, 1206 (1957).
2. C. W. Gardiner, Handbook of Stochastic Methods (Springer, New York, 1985).
3. A. Abragam, The Principles of Nuclear Magnetism (Clarendon, Oxford, 1961; Inostrannaya Literatura, Moscow, 1963).
4. R. Kubo, J. Math. Phys. 4, 174 (1963).
5. G. H. Weiss, Aspects and Applications of the Random Walk (North-Holland, Amsterdam, 1994).