<bdi><a href="https://en.wikipedia.org/wiki/en:Caspar_van_Wittel" class="extiw" title="w:en:Caspar van Wittel"><span title="landscape painter (1653-1736)">Gaspar van Wittel</span></a>
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<a rel="nofollow" class="external free" href="https://www.sothebys.com/en/auctions/ecatalogue/2005/old-master-drawings-l05040/lot.142.html">https://www.sothebys.com/en/auctions/ecatalogue/2005/old-master-drawings-l05040/lot.142.html</a> (Sotheby's).