1. Department of Mathematics and Applied Mathematics, University Crete, Heraklion, Greece
2. Institute of Applied and Computational Mathematics, Foundation for Research and Technology - Hellas (FORTH), Heraklion, Greece
3. Department of Electronic Engineering, Hellenic Mediterranean University, Chania, Greece
4. Department of Mathematical Analysis, University of La Laguna, San Cristóbal de La Laguna, Spain
5. Institute of Emerging Technologies (I-EMERGE), Hellenic Mediterranean University Research Centre (HMURC), Heraklion, Greece