1. E. Ising, Z. Phys. 31, 253 (1925).
2. H.N.V. Temperley, in: Phase Transitions and Critical Phenomena, Vol. 1, Eds.: C. Domb and M.S. Green, Academic Press 1972.
3. e.g.: K. Binder, in: Fundamental Problems in Statistical Mechanics, Ed.: E.G.D. Cohen, North Holland 1980, and: Heidelberg Colloquium on Spin Glasses, Eds. J.L. van Hemmen and I. Morgenstern, Lecture Notes in Physics 192, Springer 1983.
4. G. Toulouse, Commun. Phys. 2, 115 (1977).
5. J. Vannimenus, G. Toulouse, J. Phys. C10, L537 (1977).