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