http://www.radiology.ucsf.edu/ultrasound/

http://www.msultrasound.net/

http://drgdiaz.com/intro.shtml

http://www.answers.com/topic/diagnostic-ultrasound

http://tatediagnostic.com/index.html

http://www.diagnosticultrasound.yourmd.com/

http://shopping.yahoo.com/p:Diagnostic%20Imaging%20Ultrasound:%20Ultrasound:3005053775

http://www.nwprenatalultrasound.com/faqs.html

http://en.wikipedia.org/wiki/Ultrasound

http://www.diagnosticimaging.com/Ultrasound

http://www.accessmylibrary.com/coms2/summary_0286-22062175_ITM