1. Department of Mathematics, University of Kalyani, Kalyani 741235, India
2. Department of Mathematics, Bankura University, Bankura 722155, West Bengal, India
3. Institute of Exact and Earth Science, Federal University of Mato Grosso, Barra do Garças-MT, Brazil
4. Department of Mathematics, Institute of Science, Banaras Hindu University, Varanasi 221005, India