Mr. Terhune having a frolic with his dogs, the rightmost Collie is Wolf
Unknown author<span style="display: none;">Unknown author</span>
<cite style="font-style:normal">Duren, George Bancroft; Dodge, Mary Mapes (ed) (March 1922). "<a rel="nofollow" class="external text" href="https://archive.org/stream/stnicholasforyouv49part1rich#page/522/mode/1up/">The Sunnybank Collies</a>". <i>St. Nicholas</i> <b>49</b> (5): p. 522. New York, United States: The Century Company. Retrieved on <span class="mw-formatted-date" title="2010-06-03">2010-06-03</span>.</cite>