Olson, Storrs L; David, Normand (1 January 2014). "The gender of the tortoise genus Chelonoidis Fitzinger, 1835 (Testudines: Testudinidae)". Proceedings of the Biological Society of Washington. 126 (4): 393–394. doi:10.2988/0006-324X-126.4.393. S2CID83706022.
Olson, Storrs L; David, Normand (1 January 2014). "The gender of the tortoise genus Chelonoidis Fitzinger, 1835 (Testudines: Testudinidae)". Proceedings of the Biological Society of Washington. 126 (4): 393–394. doi:10.2988/0006-324X-126.4.393. S2CID83706022.