1. D.J. Craik, R.S. Tebble, Ferromagnetism and Ferromagnetic Domains, North Holland, Amsterdam, 1965.
2. G. van der Laan, B.T. Thole, G.A. Sawatsky, J.B. Goedkoop, J.C. Fuggle, J.M. Esteva, R. Karnatak, J.P. Remeika, H.A. Dabrowska, Phys. Rev. B 34 (1986) 6529; J.B. Goedkoop, B.T. Thole, G. van der Laan, G.A. Sawatksy, F.M.F. de Groot, J.C. Fuggle, Phys. Rev. B 37 (1988) 2086; R.J.H. Kappert, M. Sacchi, J.B. Goedkoop, M. Grioni, J.C. Fuggle, Surf. Sci. Lett. 248 (1991) L245; G. Schütz, W. Wagner, W. Wilhelm, P. Kienle, R. Zeller, R. Frahm, G. Materlik, Phys. Rev. Lett. 58 (1987) 737; G. Schütz, M. Knülle, H. Ebert, Phys. Scr. T49 (1993) 302; C.T. Chen, F. Sette, Y. Ma, S. Modesti, Phys. Rev. B 42 (1990) 7262; C.T. Chen, N.V. Smith, F. Sette, Phys. Rev. B 43 (1991) 6785.
3. H.G. Birken, C. Blessing, C. Kunz, vol. 11, ch. 12, p. 279, in E.D. Palik (Ed.), Handbook of Optical Constants of Solids, Vol. II, Academic Press, Orlando, FL, 1985, chapter 12, p. 279; vol. II, Academic Press, Boston, MA, 1991.
4. C.M. Schneider, K. Holldack, M. Kinzler, M. Grunze, H.P. Oepen, F. Schäfers, H. Petersen, K. Meinel, J. Kirschner, Appl. Phys. Lett. 63 (1993) 2532; T. Kachel, W. Gudat, K. Holidack, Appl. Phys. Lett. 64 (1994) 655.
5. W. Engel, M.E. Kordesch, H.H. Rotermund, S. Kubala, A.v. Oertzen, Ultramicroscopy 36 (1993) 16.