1. Graduate Research Assistant, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706.
2. Professor, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706.
3. Wisconsin Distinguished Professor and Chairman, Geological Engineering, Univ. of Wisconsin-Madison, Madison, WI 53706.
4. Professor Emeritus, Geology and Geophysics, Univ. of Wisconsin-Madison, Madison, WI 53706.