1. CFR (Code of Federal Regulations).2006. Title 9: Subchapter A. Animal Welfare. Office of the Federal Register Washington D.C. (http://www.aphis.usda.gov/ac/publications.html).
2. ILAR Committee on Care and Use of Laboratory Animals.1996. Guide for the Care and Use of Laboratory Animals. Institute of Laboratory Animal Resources Commission on Life Sciences National Research Council National Academy Press Washington D.C.http://www.nap.edu/readingroom/books/labrats/.