Donald H Gray

DONALD H. GRAY, PhD, is Professor of Civil and Environmental Engineering at the University of Michigan. ROBBIN B. SOTIR is President of Robbin B. Sotir & Associates, a soil bioengineering consulting firm based in Marietta, Georgia.

DONALD H. GRAY, PhD, is Professor of Civil and Environmental Engineering at the University of Michigan. ROBBIN B. SOTIR is President of Robbin B. Sotir & Associates, a soil bioengineering consulting firm based in Marietta, Georgia. See less