<bdi><a href="https://en.wikipedia.org/wiki/en:Karel_Boom" class="extiw" title="w:en:Karel Boom"><span title="Belgian painter (1858-1939)">Charles Boom</span></a>
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<a href="https://en.wikipedia.org/wiki/en:Bonhams" class="extiw" title="w:en:Bonhams"><span title="Auction house of fine art and antiques">Bonhams</span></a>:  lot number <a rel="nofollow" class="external text" href="https://www.bonhams.com/auctions/11932/lot/21/">21</a> (sale 11932, <a href="https://en.wikipedia.org/wiki/en:London" class="extiw" title="w:en:London"><span title="capital and largest city of the United Kingdom">London</span></a>, 28 June 2005)