<a href="https://en.wikipedia.org/wiki/Albert_Ballin" class="extiw" title="en:Albert Ballin">Albert Ballin</a>
Unknown author<span style="display: none;">Unknown author</span> (The photographer is unknown and not mentioned in the source.)
<i>Sport &amp; Salon</i> August 26, 1917, p.9<br><a rel="nofollow" class="external free" href="http://anno.onb.ac.at/cgi-content/anno?aid=sus&amp;datum=19170826&amp;seite=9&amp;zoom=33">http://anno.onb.ac.at/cgi-content/anno?aid=sus&amp;datum=19170826&amp;seite=9&amp;zoom=33</a>