"Equilibrium Pathologies." Archives for Sensology and Neurootology in Science and Practice. January 2004 (April 4, 2004). <http://www.vertigo-dizziness.com/english/equilibrium_pathologies.html>.
"Dizziness." The Mayo Clinic. October 10, 2002 (April 4, 2004). <http://www.mayoclinic.com/invoke.cfm?id=DS00435>.