1. Jack, F.A. and Sydney, G.C., US Patent 324 584, 1966.
2. Pollock, H.C. and Smith, A.L., US Patent 4 602 957, 1986.
3. Ward, R.W., Campbell, R.E., and Boys, W.E., US Patent 4947065, 1990.
4. Skorman, B., Chzhou, E., and Jansson, P., RF Patent 2389099, 2010.
5. Jansson, P., Advance in soft magnetic composites, Symp. on Soft Magnetic Materials 98, Barcelona, 1998, no. 7.