Citation Hunt

The Wikipedia snippet below is not backed by a reliable source. Can you find one?

Click I got this! to go to Wikipedia and fix the snippet, or Next! to see another one. Good luck!

In page János Bolyai:

"

The Babeș-Bolyai University in Cluj-Napoca, that was established in 1959, bears his name, as does the professional society of Hungarian mathematicians, the János Bolyai Mathematical Institute, at the University of Szeged. There is also a mathematical award given out every five years, named the Bolyai Prize. Bolyai is a minor character in the 1969 science-fiction/fantasy story "Operation Changeling", where his unique abilities allow the protagonists to navigate the non-Euclidean geometry of Hell.[citation needed]