References

1. Available from Arbor Scientific (http://www.arborsi.com), Cat. No. P8–1123, $15.00/pair. first citation in article
   
2. See, for example, Jorge Guala-Valverde et al., "The homopolar motor: A true relativistic engine," Am. J. Phys. 70 (10), 1052–1055 (Oct. 2002) and references therein. [ISI] first citation in article
   

1. Motional Mechanisms of Homopolar Motors & Rollers
   H. K. Wong, Phys. Teach. 47, 463 (2009)
2. Levitated Homopolar Motor
   H. K. Wong, Phys. Teach. 47, 124 (2009)
3. The Homopolar Motor and Its Evolution
   Norihiro Sugimoto et al., Phys. Teach. 44, 313 (2006)
4. Force on a Current-Carrying Wire
   Seán Stewart, Phys. Teach. 44, 245 (2006)
5. The Simplest Generator from the Simplest Motor?
   Robert Beck Clark, Phys. Teach. 44, 121 (2006)