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Mendel, F. C.  1979.  The wrist joint of two-toed sloths: its relevance to brachiating adaptations in the Hominoidea.  Journal of Morphology, 162: 413-424.

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-------- and G. F. Meritt.  1976b.  Sex ratios of Hoffmann's sloths, Choloepus hoffmanni Peters, and three-toed sloth, Bradypus infuscatus Wagler, in Panama.  American Midland Naturalist, 96(2): 472-473.

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