1. The similar phase diagram was first presented in Koon Chodendo no Ka- gaku, Report on the Research supported by Grant-in Aid for Scientific Research on Priority Areas from the Ministry of Education, Science, Sports and Culture (in Japanese), ed. by M. Tachiki, March 1994, p. 133
2. M. Sato: Physica C 263 (1996) 271
3. M. Sato: Studies of High Temperature Superconductors vol.19, ed. A. Narlikar, Nova Science Publishers INC, April 1996, p. 213
4. H. Yasuoka, T. Imai, T. Shimizu: Strong Correlation and Superconductivity, ed. H. Fukuyama, S. Maekawa, A.P. Malozemoff (Springer Series 1989 ) p. 254
5. M. Takigawa, A.P. Hammel, J.D. Thompson, R.H. Heffner, A. Fisk and K.C. Ott: Phys. Rev. B 43 (1991) 247