The southeastern corner of Vrijthof square in Maastricht, Netherlands, in 1669. To the right: Saint Servatius guest house and chapel. Pen drawing, washed in colour, by Josua de Grave, 1669. 9,5 x 15 cm. Collection: Teylers Museum, Haarlem, Netherlands.
<bdi><a href="https://en.wikipedia.org/wiki/en:Josua_de_Grave" class="extiw" title="w:en:Josua de Grave"><span title="Dutch Golden Age painter (1643-1712)">Josua de Grave</span></a>
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J G J Koreman, <i>Geteeckent tot Maestricht</i> . Maastricht, 1981 (p.59)