1. Birss, R. R., Gerber, R. and Parker, M. R. 1976.Proc. Intermag76Pittsburgh
2. Bleaney, B. I. and Bleaney, B. 1959.Electricity and Magnetism., 2nd edition, 124Oxford: Clarendon Press.
3. Brown, W. F. 1970. 48University of Minnesota Mines Experiment Station. Progress Report No. 19