Plattegrond van Riga (1735) by anonymous and erven J Ratelband and Co https://www.rawpixel.com/image/13749205/plattegrond-van-riga-1735-anonymous-and-erven-ratelband-andFree Image from public domain licensePlattegrond van het fort Dünamünde bij Riga (1735) by anonymous, erven J Ratelband and Co and Daniel de Lafeuille https://www.rawpixel.com/image/13749396/image-paper-art-patternFree Image from public domain license