1. D.H. Martin, Magnetism in Solids. Iliffe Books Ltd., London 1967.
2. H. Roos, Internal Laboratory Report No. 2664, Sandvik Coromant Research Center 1980.
3. Cobalt Monograph, Centre d'Information du Cobalt, Brussels 1960, p.75
4. G. Borelius, Ann. D- Physik Ser., 5, 20/1934/57.
5. G. Borelius, J. Andersson and K. Gullberg, I.V.A. Handlingar Nr 169, Stockholm,1943.