<bdi><a href="https://en.wikipedia.org/wiki/en:Carl_Wuttke" class="extiw" title="w:en:Carl Wuttke"><span title="German painter (1849-1927)">Carl Wuttke</span></a>
</bdi>
<a href="https://en.wikipedia.org/wiki/Christie%27s" class="extiw" title="en:Christie's">Christie's</a>, LotFinder:  entry  <a rel="nofollow" class="external text" href="https://www.christies.com/LotFinder/lot_details.aspx?intObjectID=5421546">5421546</a> (sale 5674, lot 124, London, 6 April 2011)