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Shoshani, J.; Ferretti, M. P.; Lister, A. M.; Agenbroad, L. D.; Saegusa, H.; Mol, D.; Takahashi, K. (2007). «Relationships within the Elephantinae using hyoid characters». Quaternary International. 169-170: 174–185. Bibcode:2007QuInt.169..174S. doi:10.1016/j.quaint.2007.02.003.
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Shoshani, J.; Ferretti, M. P.; Lister, A. M.; Agenbroad, L. D.; Saegusa, H.; Mol, D.; Takahashi, K. (2007). «Relationships within the Elephantinae using hyoid characters». Quaternary International. 169-170: 174–185. Bibcode:2007QuInt.169..174S. doi:10.1016/j.quaint.2007.02.003.