[1] Autonomous Univ Nuevo Leon, Dept Phys & Math Sci, San Nicolas De Los Garza 66450, Nuevo Leon, Mexico
[2] Univ Glamorgan, Fac Adv Technol, Dept Comp & Math Sci, Pontypridd CF37 1DL, M Glam, Wales
[3] Victoria Univ, Sch Sci & Engn, Melbourne, Vic 8001, Australia
[4] Univ S Australia, Sch Math & Stat, Mawson Lakes 5095, Australia