References
- Roman Badora, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: robadora@math.us.edu.pl
- Mihály Bessenyei, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: besse@science.unideb.hu
- Zoltán Boros, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: boros@science.unideb.hu
- Pál Burai, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: burai.pal@inf.unideb.hu
- Borbála Fazekas, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: borbala.fazekas@science.unideb.hu
- Włodzimierz Fechner, Łódz University of Technology, Wólczanska 215, 90-924 Łódz, Poland; e-mail: wlodzimierz.fechner@p.lodz.pl
- Zywilla Fechner, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: zfechner@math.us.edu.pl
- György Gát, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: gat.gyorgy@science.unideb.hu
- Roman Ger, Univeristy of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: romanger@us.edu.pl
- Attila Gilányi, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: gilanyi.attila@inf.unideb.hu
- Eszter Gselmann, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: gselmann@science.unideb.hu
- Tibor Kiss, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: kiss.tibor@science.unideb.hu
- Zygfryd Kominek, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: zkominek@math.us.edu.pl
- Gábor Lucskai, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: gabor.lucskai@science.unideb.hu
- Radosław Łukasik, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: rlukasik@math.us.edu.pl
- Judit Makó, University of Miskolc, 3515 Miskolc-Egyetemváros, Hungary; e-mail: matjudit@uni-miskolc.hu
- Gyula Maksa, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: maksa@science.unideb.hu
- Janusz Morawiec, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: morawiec@math.us.edu.pl
- Gergo Nagy, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: nagyg@science.unideb.hu
- Andrzej Olbrys, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: andrzej.olbrys@wp.pl
- Zsolt Páles, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: pales@science.unideb.hu
- Maciej Sablik, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: maciej.sablik@us.edu.pl
- Ekaterina Shulman, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: ekaterina.shulman@us.edu.pl
- Justyna Sikorska, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: justyna.sikorska@us.edu.pl
- Patrícia Szokol, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: szokolp@science.unideb.hu
- Tomasz Szostok, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: tszostok@math.us.edu.pl
- Filip Turobos, Łódz University of Technology, Skorupki 6/8, 90-924 Łódz, Poland; e-mail: 180962@edu.p.lodz.pl
- Paweł Wójcik, Pedagogical University of Cracow, Podchorazych 2, 30-084
- Kraków; Poland; e-mails: pawel.wojcik@up.krakow.pl; pwojcik@up.krakow.pl
- Amr Zakaria, University of Debrecen, Pf. 400, 4002 Debrecen, Hungary; e-mail: amr.zakaria@edu.asu.edu.ag
- Thomas Zürcher, University of Silesia, ul. Bankowa 14, 40-007 Katowice, Poland; e-mail: thomas.zurcher@us.edu.pl