[1] Univ Catania, Dept Phys & Astron Ettore Majorana, Via S Sofia 64, I-95125 Catania, Italy
[2] Ist Nazl Fis Nucl, Sez Catania, Via S Sofia 64, I-95125 Catania, Italy
[3] Namur Inst Complex Syst, NaXys, Rue Grafe 2, B-5000 Namur, Belgium
[4] Univ Namur, Dept Math, Rue Grafe 2, B-5000 Namur, Belgium
[5] Univ Fed Rio de Janeiro, Dept Appl Math, Math Inst, Ave Athos da Silveira Ramos 149, BR-21941909 Rio De Janeiro, Brazil
[6] Univ Catania, Dept Elect Elect & Comp Sci Engn, Viale Andrea Doria 6, I-95125 Catania, Italy
[7] Queen Mary Univ London, Sch Math Sci, Mile End Rd, London E1 4NS, England
[8] Complex Sci Hub, Josefstadter Str 39, A-1080 Vienna, Austria
[9] Consiglio Nazl Ric IASI CNR, Ist Anal Sistemi Informat A Ruberti, Via Taurini 19, I-00185 Rome, Italy