1. Ecole de Génie Rural (EGR), 01 BP 55 Kétou, Benin
2. Institut de Mathématiques et de Sciences Physiques (IMSP), 01 BP 613 Porto-Novo, Benin
3. Ecole Doctorale des Sciences Exactes et Appliquées, UAC, Bénin
4. Department of Mathematics, Egra S. S. B. College, Purba Medinipur 721429, West Bengal, India
5. National Research Nuclear University, MEPHI (Moscow Engineering Physics Institute), Moscow 115409, Russia
6. Université de Paris, CNRS, Astroparticule et Cosmologie, F-75013 Paris, France
7. Institute of Physics, Southern Federal University, Rostov on Don 344090, Russia
8. Department of Physics, Government College of Engineering and Ceramic Technology, Kolkata 700010, West Bengal, India
9. Satyabharati Vidyapith, Nabapally, Barasat, North 24 Parganas, Kolkata 700126, West Bengal, India