1. Department of Mathematics, Indian Institute of Engineering Science and Technology, Shibpur, Howrah 711103, India
2. Department of Applied Mathematics, Maulana Abul Kalam Azad University of Technology, West Bengal, Haringhata, Nadia 741249, West Bengal, India
3. Department of Information Technology, Dr. B.C. Roy Engineering College, Durgapur, West Bengal, India
4. Department of Mathematics, The University of Burdwan, Golapbag, Burdwan, West Bengal, India