Roca, Alfred L.; Georgiadis, N; Pecon-Slattery, J; O'Brien, SJ (24 August 2001). "Genetic evidence for two species of elephant in Africa". Science. 293 (5534): 1473–7. doi:10.1126/science.1059936. PMID11520983.
Roca, Alfred L.; Georgiadis, N; Pecon-Slattery, J; O'Brien, SJ (24 August 2001). "Genetic evidence for two species of elephant in Africa". Science. 293 (5534): 1473–7. doi:10.1126/science.1059936. PMID11520983.