1. U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Reproductive Toxicology Division, Research Triangle Park, North Carolina, USA
2. U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Environmental Carcinogenesis Division, Research Triangle Park, North Carolina, USA
3. Applied Biosystems, 850 Lincoln Centre Dr, Foster City, California, USA