Offered for sale by <a href="https://en.wikipedia.org/wiki/Abbott_and_Holder" class="extiw" title="en:Abbott and Holder">Abbott and Holder</a> in December 2019, when it was described as "CALLOW William O.W.S. (1812-1908) A View of Mainz. Ink and watercolour. Circa 1835. Exhibited: Colnaghi. 5.5x11 inches."
<bdi><a href="https://en.wikipedia.org/wiki/en:William_Callow" class="extiw" title="w:en:William Callow"><span title="painter from Great Britain (1812-1908)">William Callow</span></a>
</bdi>
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