1. V. E. Gasumyants, V. I. Kaidanov, and E. V. Vladimirskaya, Physica C 248, 255 (1995).
2. V. É. Gasumyants, S. A. Kaz’min, V. I. Kaidanov, V. I. Smirnov, Yu. M. Baikov, and Yu. P. Stepanov, Sverkhprovodimost’ (KIAE) 4, 1280 (1991).
3. E. V. Vladimirskaya, V. É. Gasumyants, and I. B. Patrina, Fiz. Tverd. Tela (St. Petersburg) 37, 1990 (1995) [Phys. Solid State 37, 1084 (1995)].
4. J. M. Tarascon, P. Barboux, P. F. Miceli, L. H. Greene, G. W. Hall, M. Eibschutz, and S. A. Sunshine, Phys. Rev. B 37, 7458 (1988).
5. R. S. Howland, T. H. Geballe, S. S. Laderman, A. Fischer-Colbrie, M. Scott, J. M. Tarascon, and P. Barboux, Phys. Rev. B 39, 9017 (1989).