1. K. Kasuga and M. Tsutsui, Coord. Chem. Rev.32, 67 (1980).
2. B. D. Berezin, “Coordination Compounds of Porphyrins and Phthalocyanines,” Nauk, Moscow (1978), K. M. Smith (edi- tor) “Porphyrins and Metalloporphyrins,” Elsevier, New York (1975).
3. H. Meier, “Organic Semiconductors,”Verlag Chemie, Wein- heim, (1974).
4. A. B. P. Lever, Adv. Inorg. Radiochem. 7, 28 (1965).
5. A. A. Berlin and A. I. Sherle, Inorg. Macromol, Rev.1, 235 (1975).