1. Department of Mathematics, Bajkul Milani Mahavidyalaya, Kismat Bajkul, West Bengal, Purba Medinipur 721655, India
2. School of Mathematics, Thapar Institute of Engineering and Technology, Punjab, Patiala 147004, India
3. Independent Researcher, West Bengal, Purba Medinipur 721652, India
4. Barkhali High School, Barkhali, Amira, Diamond Harbour, South 24 Parganas 743368, India