1. G. Eilenberger,Z. Phys. 214, 195 (1968).
2. L. Kramer and W. Pesch, inLow Temperature Physics LT-13 (Proc. 13th Int. Conf. on Low Temp. Phys., Boulder, Colorado, 1972) (Plenum, New York, 1973);Solid State Commun. 12, 549 (1973); and to be published.
3. A. L. Fetter and P. C. Hohenberg, inSuperconductivity, R. D. Parks, ed. (Marcel Dekker, New York, 1969), Vol. 2.
4. L. Tewordt,Z. Phys. 184, 319 (1965); L. Neumann and L. Tewordt,Z. Phys. 189, 55 (1966);191, 73 (1966).
5. K. Maki,Physics 1, 21 (1964).