1. Department of Mathematics, Kabi Jagadram Roy Government General Degree College, Mejia, Bankura, India
2. Department of Physics, Government General Degree College at Kushmandi, Dakshin Dinajpur, West Bengal, India
3. Department of Mathematics, Sikkim Manipal Institute of Technology, Sikkim Manipal University, Rangpo, Sikkim, India
4. Department of Mathematics, Visva-Bharati University, Bolpur, West Bengal, India