↑Gray,J.E. (1873) Additional notes on the form of the bones in the sternum of very young tortoises, and their development., Ann. Mag. Nat. Hist. (4) 12: 319-323
↑ 3.03.1Gray, J. E. (1831) A synopsis of the species of Class Reptilia. In: Griffith, E & E. Pidgeon: The animal kingdom arranged in conformity with its organisation by the Baron Cuvier with additional descriptions of all the species hither named, and of many before noticed [Vol. 9, Whittaker, Treacher and Co., London: 481 + 110 pp.
↑ 4.04.1Bisby F.A., Roskov Y.R., Orrell T.M., Nicolson D., Paglinawan L.E., Bailly N., Kirk P.M., Bourgoin T., Baillargeon G., Ouvrard D. (ed.) (2011). "Species 2000 & ITIS Catalogue of Life: 2011 Annual Checklist". Species 2000: Reading, UK. Ginkuhà 24 Septyembre 2012.CS1 maint: multiple names: authors list (link) CS1 maint: extra text: authors list (link)