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2. B.R. Coles, Proc. of the Geilo Institute on Multicritical Phenomena, 1983, to be published (Plenum).
3. G. Parisi, Phys. Rev. Letters 50 (1983) 1946.
4. C. De Dominicis, A.P. Young, J. Phys. A 16 (1983) 2063.
5. C.L. Henley, to appear in Phys. Rev. B.