1. Laboratory of Atomic, Molecular and Nuclear Physics, Department of Physics, Faculty of Science, University of Yaounde I, P. O. Box 812, Yaounde, Cameroon
2. The Nuclear Technology Section (NTS), Institute of Geological and Mining Research, P. O. Box 4110, Yaounde, Cameroon
3. Bertoua Higher Teachers’ Training College, Department of Physics, University of Bertoua, P. O. Box 55, Bertoua, Cameroon