1. V.J. Emery and S.A. Kivelson, Phys. Rev.Lett. 64, 475 (1990); ibid. Phys.Rev.B 42, 4523 (1990); ibid., Physica C 209 597 (1993), ibid in “Phase separation in Cuprate Superconductors” Eds. K.A.Muller and G.Bendek (World Scientific, 1992)
2. E. Sigmund, V. Hizhnyakov and G. Seibold in “Phase separation in Cuprate Superconductors” Eds. K.A. Muller and G. Bendek (World Scientific, 1992)
3. C.Di Castro and M. Grilli, in “Phase separation in Cuprate Superconductors” Eds. K.A. Muller and G. Bendek (World Scientific, 1992)
4. The proceedings of the Erice workshop were published as “Phase separation in Cuprate Superconductors” Eds. K.A. Muller and G. Bendek (World Scientific, 1992)
5. The proceedings of the Cottbus workshop were published as “Phase separation in Cuprate Superconductors” Eds. E. Sigmund and K.A. Muller (World Scientific, 1994)