1. Pfizer, Inc., Groton, Connecticut 06340, USA
2. Merck Research Laboratories, West Point, Pennsylvania 19586 USA
3. Pathology Branch, Center for Food Safety and Applied Nutrition, FDA, College Park, Maryland 20740, USA
4. U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711, USA
5. Charles River Laboratories, Senneville, Quebec H9X 3R3, Canada
6. Merck and Company, Inc., West Point, Pennsylvania 19486, USA
7. Wyeth Research, Chazy, New York 12921 USA
8. Health Canada Ottawa, Ontario K1A 0L2, Canada
9. Sanofi-Aventis, Porcheville 78440, France
10. Vet Path Services, Inc., Cincinnati, Ohio 45249, USA
11. Albert Einstein College of Medicine Bronx, New York 10461, USA
12. Purdue University, West Lafeyette, Indiana 47907, USA