1. Department of Mathematics, Cotton University, Panbazar , Guwahati-781001 , Assam , India
2. University of Kragujevac, Faculty of Hotel Management and Tourism, Vojvodjanska bb , 36210 Vrnjacka Banja , Serbia
3. Department of Mathematics, Gilan-E-Gharb Branch, Islamic Azad University , Gilan-E-Gharb , Iran
4. Department of Medical Research, China Medical University Hospital, China Medical University (Taiwan) , Taichung 40001 , Taiwan
5. Department of Mathematics, Azadshahr Branch, Islamic Azad University , Azadshahr , Iran