Affiliation: | (1) Department of Applied Mathematics, Faculty of Electrical Engineering and Computing, Unska 3, 10000 Zagreb, Croatia;(2) Dipartimento di Matematica, Università di Torino, Via Carlo Alberto, 10, 10123 Torino, Italia;(3) Faculty of Textile Technology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia |