• [Wiki] https://en.wikipedia.org/wiki/Bearded_seal.
• [AnAge] http://genomics.senescence.info/species/entry.php?species=Erignathus_barbatus.
• [KovaLyde] http://www.npolar.no/en/species/bearded-seal.html.
• [AndeHjel1999] Andersen, M., Hjelset, A. M., Gjertz, I., Lydersen, C., and Gulliksen, B. (1999). Growth, age at sexual maturity and condition in bearded seals (Erignathus barbatus) from Svalbard, Norway. Polar Biology, 21:179--185.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.