1. P.G. de Gennes, Rev. Mod. Phys.36, 225 (1964).
2. G. Deutscher and P.G. de Gennes in Parks, “Superconductivity”, Vol. 1 (1969).
3. I.O. Kulik, Zh. Eksp. Theor. Phys.,57, 1745 (1969) [Sov. Phys. JETP30, 944 (1970)].
4. K.K. Likharev, Rev. Mod. Phys.51, 101 (1979).
5. A.D. Zaikin, and G.F. Zharkov, Fiz. Nizk. Temp.7, 375 (1981) [Sov. J. Low Temp. Phys.7, 184 (1981)]; A.D. Zaikin, in:Nonequilibrium Superconductivity, ed. V.L. Ginzburg (Nova Science, N.Y., 1986), p. 57.