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Lerner, H.R.L.; Mindell, D.P. (2005). "Phylogeny of eagles, Old World vultures, and other Accipitridae based on nuclear and mitochondrial DNA". Molecular Phylogenetics and Evolution. 37 (37): 327–346. doi:10.1016/j.ympev.2005.04.010. PMID15925523.
Lerner, H.R.L.; Mindell, D.P. (2005). "Phylogeny of eagles, Old World vultures, and other Accipitridae based on nuclear and mitochondrial DNA". Molecular Phylogenetics and Evolution. 37 (37): 327–346. doi:10.1016/j.ympev.2005.04.010. PMID15925523.