1. Public Health Service Policy on Humane Care and Use of Laboratory Animals, IV.C.1.b. (US Department of Health and Human Services, Bethesda, MD, 1986; revised 2015, NIH Publication No. 15-8013
http://grants.nih.gov/grants/olaw/references/phspol.htm
).
2. Institute for Laboratory Animal Research. Guide for the Care and Use of Laboratory Animals 8th edn. p. 26 (National Academies Press, Washington, DC, 2011).