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den Tex, R.-J.; Leonard, J. A. (2013). "A molecular phylogeny of Asian barbets: Speciation and extinction in the tropics". Molecular Phylogenetics and Evolution. 68 (1): 1–13. doi:10.1016/j.ympev.2013.03.004. PMID23511217.
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pubmed.ncbi.nlm.nih.gov
den Tex, R.-J.; Leonard, J. A. (2013). "A molecular phylogeny of Asian barbets: Speciation and extinction in the tropics". Molecular Phylogenetics and Evolution. 68 (1): 1–13. doi:10.1016/j.ympev.2013.03.004. PMID23511217.