(A) Skull of Mylodon darwinii as featured in Reinhardt (1879). (B) Skull of Glossotherium robustum as featured by Owen (1842).
Reinhardt, J. T., Richard Owen
<a rel="nofollow" class="external free" href="http://www.slothsearch.com/about/research/taxonomy">http://www.slothsearch.com/about/research/taxonomy</a> A. Reinhardt, J. T. 1879. Description of the skull of a giant sloth, Gry-potherium darwini. Videnskavernes Selskabs Skrifter. 5 Raekke.Naturvidensakbelig og Mathematisk Afdeling 12:351–381 B. Owen (1842)