1. I. A. Campbell and A. Fert, Ferromagnetic materials, in: Transport Properties of Ferromagnets,edited by E. P. Wohlfarth, vol 3 (North Holland, Amsterdam, 1982), p. 748.
2. G. Binash et al., Phys. Rev. B 39, 4828 (1989).
3. M. N. Baibich et al., Phys. Rev. Lett. 61, 2472 (1988).
4. P. M. Levy, Solid State Phys. Ser. 47, 367 (1994).
5. M. A. M. Gijs and G. E. W. Bauer, Adv. Phys. 46, 285 (1997).