1. ESIME-Zacatenco, Instituto Politécnico Nacional, Ciudad de México , Mexico.
2. Facultad de Informática y Matemática, Universidad de Holguín , Holguín, Cuba.
3. Department of Mathematics, Center for Research and Development in Mathematics and Applications, University of Aveiro , Aveiro, Portugal.
4. Faculty of Sciences and Literature, Department of Mathematics, Izmir University of Economics , Izmir, Turkey.