AMSil, Redakcja. 2004. “Report of Meeting. The Fourth Debrecen-Katowice Winter Seminar on Functional Equations and Inequalities February 4-7, 2004 Matráháza, Hangary”. Annales Mathematicae Silesianae 18 (September), 65-75. https://www.journals.us.edu.pl/index.php/AMSIL/article/view/14092.