1. P. G. de Gennes,Superconductivity of Metals and Alloys (Benjamin, New York, 1966), pp. 48?55.
2. R. R. Hake,Phys. Rev. 166, No. 2, 471 (1968).
3. R. Ehrat and L. Rinderer,Proc. 11th. Intern. Conf. Low Temp. Phys. (St. Andrews, Scotland, 1968), pp. 1041?1044.
4. R. Ehrat and L. Rinderer,Phys. Letters 29A, 712 (1969).
5. V. L. Ginzburg and L. D. Landau,Soviet Phys.?JETP 20, 1064 (1950).