1. Department of Mathematics, Karnatak University, Dharwad 580003, India
2. Department of Mathematics, Faculty of Science, Davangere University, Shivagangothri, Davangere 577002, India
3. Department of Mathematics,Faculty of Arts and Sciences, Çankaya University, Ögretmenler Cad., Ankara 1406530, Turkey; Department of Mathematics, Institute of Space Sciences, Magurele, Bucharest 06790, Romania; Department of Medical Research,China Medical University Hospital, China Medical University, Taichung 404, Taiwan