This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Johann Hnig. Johann Hnig im Studienjahr Rektor des Polytechnischen Institutes Wien Eine Sammlung von auerordentlicher Geschlossenheit ISBN Festschrift Jahre TU Wien Band Wenzel Ottokar Noltsch oeaw ac at xml Portrt aus dem Jahr other versions PDold paintings Johann Hnig Wenzel Ottokar Noltsch
Page 2023 Free-images.com. All images are Public Domain