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.
FNul a. en Prof Nusl Czech astronomer cs Prof Nul esk astronom Commercial photo from my family archive Langhans PDold Frantiek Nul Jan Nepomuk Langhans
Page 2023 Free-images.com. All images are Public Domain