1. Orthopaedic Products Division, 3M Company, St. Paul, Minn. 55144
2. Department of Civil Engineering, Middle East Technical University, Ankara, Turkey
3. Bioengineering Program, University of Michigan, Ann Arbor, Mich. 48109
4. Highway Safety Research Institute, University of Michigan, Ann Arbor, Mich. 48109
5. Department of Obstetrics and Gynecology, University of Illinois, Chicago, Ill. 60612