permanent magnets made from alloys of rare earth elements
- Ferrofluid: a liquid that becomes strongly magnetized in the presence of a magnetic field.
- McCaig, Malcolm 1977. Permanent magnets in theory and practice. New York: Wiley. ISBN 0-7273-1604-4
- Magnetostrictive materials change their shape or dimensions during the process of magnetization
- Furlani, Edward P. 2001. Permanent magnet and electromechanical devices: materials, analysis and applications. Academic Press Series in Electromagnetism. ISBN 0-12-269951-3