1. Heck, C. (1974) Magnetic Materials and their Applications, Crane and Russak & Co., New York.
2. Three-volume series,1982
3. Warbug, E. (1981) Ann. Physik, 13, 141.
4. Ewing, J. A. (1900) Magnetic Induction in Iron and other Metals, 3rd edn, The Electrician Publishing Co., London, 1900,
5. Ewing, J. A. (1882) Proc. Roy. Soc., 220, 39.