AMSilR. (2001). Report of Meeting. The First Katowice-Debrecen Winter Seminar on Functional Equations, February 7-10, 2001, Cieszyn, Poland. Annales Mathematicae Silesianae, 15, 87-102. Retrieved from https://journals.us.edu.pl/index.php/AMSIL/article/view/14118