http://www.springerlink.com/content/62k50g430508511q/?p=c238e2aa637549acbaa4312ebaaaf8a5&pi=1 -- ========================================================== Andinet A. Enquobahrie, PhD R&D Engineer Kitware Inc. 28 Corporate Drive Clifton Park, NY 12065-8662 Phone: 518-371-3971 x124 www.kitware.com