Signature (in the stone) by <b>Carl Friedrich Irminger</b> (1813–1863), Swiss draftsman, lithographer and engraver.
<bdi><a href="https://en.wikipedia.org/wiki/en:Carl_Friedrich_Irminger" class="extiw" title="w:en:Carl Friedrich Irminger"><span title="Swiss draughtsman, lithographer and engraver">Carl Friedrich Irminger</span></a>
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<bdi><a href="https://www.wikidata.org/wiki/Q190255" class="extiw" title="d:Q190255"><span title="cantonal and municipal library in Solothurn (Switzerland)">Zentralbibliothek Solothurn</span></a>
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