[1] Univ Nac Rio Cuarto, Dept Matemat, FCEFQyN, Ruta 36 Km 601, RA-5800 Rio Cuarto, Argentina
[2] Chengdu Univ Informat Technol, Coll Appl Math, Chengdu 610225, Sichuan, Peoples R China
[3] Jagiellonian Univ Krakow, Chair Optimizat & Control, Ul Lojasiewicza 6, PL-30348 Krakow, Poland
[4] Univ Austral, Dept Matemat, CONICET, FCE, Paraguay 1950,S2000FZF, Rosario, Argentina