Affiliation: | 1. Department of Mathematics, Faculty of Arts and Science, Nam?k Kemal University, , 59030 Tekirda?, Turkey;2. Department of Mathematics, Faculty of Arts and Science, Yildiz Technical University, , 34210 Davutpasa, Istanbul, Turkey;3. Department of Mathematical Engineering, Faculty of Chemistry and Metallurgy, Yildiz Technical University, , Istanbul, Turkey |