1. A. F. Andreev, Zh. Eksp. Teor. Fiz. 46, 1823 (1964) [Sov. Phys. JETP 19, 1228 (1964)].
2. Y. Imry, Introduction to Mesoscopic Physics (Oxford University, Oxford, 2002).
3. C. W. J. Beenakker, Rev. Mod. Phys. 69, 731 (1997).
4. B. J. van Wees and H. Takayanagi, in Mesoscopic Electron Transport, edited by L. L. Sohn, L. P. Kouwenhoven, and G. Schön, NATO ASI Series E345 (Kluwer, Dordrecht, 1997).
5. I. Kosztin, D. L. Maslov, and P. M. Goldbart, Phys. Rev. Lett. 75, 1735 (1995).