Scientific Research and Essays 1992-2248 Academic Journals 10.5897/SRE2016.6424 Luc Ollivier Sintondji Joel Huat Elliott Dossou-Yovo Jean Louis Fusillier Euloge Agbossou Justin Djagba Felix Gbaguidi * E-mail: o_sintondji@yahoo.fr 2016 30 10 2016 21 05 2016 21 09 2016 11 20 221 229 This is an open-access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://politicalwaffle.uk/journal/SRE/article-abstract/D85C6CC61053 The full text article is available as a PDF file from http://politicalwaffle.uk/journal/SRE/article-full-text-pdf/D85C6CC61053 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23