Meyer-Rochow, Victor Benno (1989). "A report of webbed feet in a mature axolotl Siredon mexicanum and remarks on webbed feet in Urodela generally". Amphibia-Reptilia. 10: 89–92. doi:10.1163/156853889x00340.
Nenad Tomić; et al. (2011), "Atavisms: Medical, Genetic, and Evolutionary Implications", Perspectives in Biology and Medicine, 54 (3): 332–353, doi:10.1353/pbm.2011.0034, PMID21857125