1. P. Bruno, Phys. Rev. B49, 13231 (1994).
2. Z.-P. Shi, Rajiv R.P. Singh, and B.M. Klein, Europhys. Lett. 29, 585 (1995).
3. J.E. Mattson, S. Kumar, E.E. Fullerton, S.R. Lee, C.H. Sowers, M. Grimsditch, S.D. Bader and F.T. Parker, Phys. Rev. Lett. 71, 185 (1993); K. Inomata, K. Yusu, and Y. Saito, Jpn. J. Appl. Phys. 33, L1670 (1994).
4. A. Chaiken, R.P. Michel, and M.A. Wall, Phys. Rev. B, submitted.
5. R.F.C. Farrow, G.R. Harp, R.F. Marks, T.A. Rabedeau, J. Cryst. Growth 133, 47 (1993).
6. C.L. Foiles, M.R. Franklin, and R. Loloee, Mat. Res. Soc. Proc. 382, to be published (1995).
7. E.E. Fullerton, I.K. Schuller, H. Vanderstraeten, and Y. Bruynseraede, Phys. Rev. B 45, 9292 (1992); J.A. Borchers, M.B. Salamon, R.W. Erwin, J.J. Rhyne, R.R. Du and C.P. Flynn, Phys. Rev. B43, 3123 (1991).
8. J.J. Krebs, P. Lubitz, A. Chaiken, and G.A. Prinz, Phys. Rev. Lett. 63, 1645 (1989).
9. S.S.P. Parkin, Phys. Rev. Lett. 67, 3598 (1991).
10. R.P. Michel and A. Chaiken, to be published.
11. J.C. Slonczewski, Phys. Rev. Lett. 67, 3172 (1991).