Hazou, Eyakifama; Department of Physics, Faculty of Science, University of Lomé, P.O. Box 1515, Lomé, Togo > Laboratoire de Physique des Matériaux et des Composants à Semi-conducteurs (LPMCS), University of Lomé, P.O. Box 1515, Lomé, Togo
Nguelem Mekongtso, Eric Jilbert; Department of Physics, Faculty of Science, University of Douala, P.O. Box 24157, Douala, Cameroon
Ndontchueng Moyo, Maurice; National Radiation Protection Agency, P.O. Box 33732, Yaoundé, Cameroon
Beyala Ateba, Jean Felix; National Radiation Protection Agency, P.O. Box 33732, Yaoundé, Cameroon
Tchakpele; Department of Physics, Faculty of Science, University of Lomé, P.O. Box 1515, Lomé, Togo