First Author:   Louis-Joel Basneouinde Diendere Thomas SANKARA University dienlouiss@gmail.com   01 BP 3755 Ouagadougou 01 OUAGADOUGOU, 01 BP 3755, Burkina Faso   00 226 74 82 91 98(Phone) 00 226 74 82 91 98(Fax) www.uts.bf Second Author: Achille Augustin Diendere Thomas SANKARA University hchille@yahoo.fr   12 BP 417 OUAGADOUGOU, 12 BP 417, Burkina Faso   00 226 70 15 75 38(Phone)   www.uts.bf Third Author: Jude Comlanvi Eggoh University of Abomey-Calavi jude.eggoh@gmail.com   10 BP 110 COTONOU, 10 BP 110, BENIN   00 229 97 82 62 89(Phone)