1. S. Feeeara, R. Gatto, A. F. Grillo andG. Parisi:Nucl. Phys.,49 B, 77 (1972).
2. S. Feeeara, E. Gatto, A. F. Grillo andG. Parisi:Nuovo Cimento,19 A, 667 (1974).
3. G. Mack: to appear inRenormalization and Symmetry in Field Theory, edited byE. Caianiello (New York, N.Y.);V. Dohrev, G. Mack, V. Petrova, S. Petrova andI. T. Todorov: Dubna preprint E2-7977 (1974) andSpringer Lecture Notes in Physics (to appear).
4. A. A. Migdal: Landau Institute preprint (1972).
5. A. M. Polyakof: Landau Institute preprint, Cernogolovsk (1973).