Sauer, Ursula G., et al. “Revised Tables for the Collection of Statistical Information on the Number of Animals Used in Experiments and Other Scientific Purposes in the European Union”. ALTEX - Alternatives to Animal Experimentation, vol. 15, no. 3, Aug. 1998, pp. 144-6, https://www.altex.org/index.php/altex/article/view/1557.