<i>Anthracoceros montani</i> (Oustalet, 1880)<br>
Plate from "A monograph of the Bucerotidæ, or family of the hornbills".
Taylor and Francis, 1882 - Biodiversity Heritage Library
CC BY 2.0
<a rel="nofollow" class="external free" href="https://www.flickr.com/photos/biodivlibrary/7090227813/">https://www.flickr.com/photos/biodivlibrary/7090227813/</a>