1. Y. Kitaoka, K. Ishida, T. Kobayashi, K. Amaya and K. Asayama: Physica C, 153, 733 (1988).
2. A. Rigamonti, F. Borsa, M. Corti, T. Rega, J. Ziolo and G. Flor: Proceedings of the XXIV Ampére Meeting, Pozman, 1988 (North Holland, Amsterdam, to be published).
3. See various contributions in Local Properties at Phase Transitions, edited by K. A. Müller and A. Rigamonti (North Holland, Amsterdam, 1976); see also F. Borsa and A. Rigamonti: in Magnetic Resonance at Phase Transitions, edited by F. J. Owens, C. P. Poole and H. A. Farah (Academic Press, New York, N.Y., 1979).
4. R. J. Birgeneau, D. R. Gabbe, H. P. Jenssen, M. A. Kastner, P. J. Picone, T. R. Thurston, G. Shirane, Y. Endoh, M. Sato, K. Yamada, Y. Hidaka, M. Oda, Y. Enomoto, M. Suzuki and T. Murakami: Phys. Rev. B, 38, 6614 (1988).
5. K. B. Lyons, P. A. Fleury, J. P. Remeika, A. S. Cooper and T. J. Negran: Phys. Rev. B, 37, 2353 (1988); Phys. Rev. Lett., 60, 732 (1988).