1. For reviews on surface critical phenomena see K. Binder in Phase Transitions and Critical Phenomena, Vol. 8, p. 1 (1983), C. Domb and J.L. Lebowitz eds., Academic Press, London; S. Diehl, ibid, Vol.
2. S- Dietrich in Phase Transitions and Critical Phe-nomena,C. Domb and J.L. Lebowitz eds (Academic Press, New York, 1988), Vol. 12; C. Domb and J.L. Lebowitz eds (Academic Press, New York, 1988), Vol. 12
3. M. Schick in Les Houches, Session XLVIII -Liquids at Interfaces,J. Charvolin, J. F. Joanny, and J. Zinn-Justin eds.(Elsevier Science Publishers B.V., 1990).
4. F. Schmid, Surface order in body centered cubic alloys. Zeitschr. f. Phys. B 91, 77 (1993).
5. S. Krimmel, W. Donner, B. Nickel, and H. Dosch,Surface segregation induced critical phenomena at FeCo(001) surfaces Phys. Rev. Lett.78, 3880 (1997).