Kovács, Z., Herendiné Kónya, E.: How do novices and experts approach an open problem?. In: Towards new perspectives on mathematics education. Eds.: Zdenka Kolar-Begović Ružica Kolar-Šuper Ljerka Jukić Matić, Element, Osijek, 245-260, 2019. ISBN: 9789531975179