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Georges Cuvier, Edward Blyth, Robert Mudie, George Johnston, John Obadiah Westwood, William Benjamin Carpenter, The Animal Kingdom: Arranged After Its Organization, Forming a Natural History of Animals, and an Introduction to Comparative Anatomy, 1851, p. 171
Sievwright, H (2016). "The feather structure of Oriental honey buzzards (Pernis ptilorhynchus) and other hawk species in relation to their foraging behavior". Zoological Science. 33 (3): 295–302. doi:10.2108/zs150175. PMID27268984. S2CID21903642.
Sievwright, H (2016). "The feather structure of Oriental honey buzzards (Pernis ptilorhynchus) and other hawk species in relation to their foraging behavior". Zoological Science. 33 (3): 295–302. doi:10.2108/zs150175. PMID27268984. S2CID21903642.
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Sievwright, H (2016). "The feather structure of Oriental honey buzzards (Pernis ptilorhynchus) and other hawk species in relation to their foraging behavior". Zoological Science. 33 (3): 295–302. doi:10.2108/zs150175. PMID27268984. S2CID21903642.