• [Wiki] http://en.wikipedia.org/wiki/Centrochelys_sulcata.
• [ADW] https://animaldiversity.org/accounts/Geochelone_sulcata/.
• [AnAge] http://genomics.senescence.info/species/entry.php?species=Centrochelys_sulcata.
• [Kooy2010] Kooijman, S. (2010). Dynamic Energy Budget theory for metabolic organisation. Cambridge Univ. Press, Cambridge.
• [RitzGrieb2010] Ritz, J., Griebeler, E. M., Huber, R., and Clauss, M. (2010). Body size development of captive and free-ranging African spurred tortoises (Geochelone sulcata): high plasticity in reptilian growth rates. Herpetological Journal, 20:213--216.