1. Alstrup, A. K. O., & Hansen, A. K. (2009). Status over forbruget af forsøgsdyr siden år 2000. Ugeskrift for Laeger, 171(43), 3088.
2. Aristotle, (2004). On the parts of animals (originally around 350 BC). Whitefish, Montana: Kessinger Publication Co.
3. Arnold, G. W. (1985). Associations and social behaviour. In A. F. Fraser (Ed.), Ethology of farm animals (pp. 233–248). New York: Elsevier.
4. Bekoff, M. (2000). Animal emotions: Exploring passionate natures. BioScience, 50, 861–870.
5. Broom, D. M., & Johnson, K. G. (1993). Stress and animal welfare. London: Chapman & Hale.