1. Litron Laboratories; Rochester; New York
2. Gentronix Ltd. and University of Manchester; Manchester; United Kingdom
3. Janssen Research and Development, A Division of Janssen Pharmaceutical; Genetic and Exploratory Toxicology; Beerse; Belgium
4. Novartis Institutes for Biomedical Research, Preclinical Safety; Genetic Toxicology and Safety Pharmacology; Basel; Switzerland