1. Zeng, H., Li, J., Liu, J. P., Wang, Z. L. & Sun, S. Nature 420, 395–398 (2002).
2. Skomski, R. & Coey, J. M. D. Permanent Magnetism (Inst. Physics, Bristol, 1999).
3. Rodewald, W. et al. in Rare Earth Magnets and Their Applications (eds Hadjipanayis, G. C. & Bonder, M. J.) 25–36 (Rinton, Princeton, 2002).
4. Skomski, R. & Coey, J. M. D. Phys. Rev. B 48, 15812–15816 (1993).
5. Kneller, E. F. & Hawig, R. IEEE Trans. Mag. 27, 3588–3600 (1991).