First Author:   Marietta Yilen University of Bamenda yyilen@yahoo.com   yyilen@yahoo.com , Cameroon   +237677032044(Phone) +237677032044(Fax) Second Author: Mekam Pouatcha Mathurin Aimé University of Bamenda mekampouatcha@yahoo.fr   Bamenda, Cameroon   +237655213256(Phone)   Third Author: Ethel Selamo University of Bamenda etheldze@yahoo.com   etheldze@yahoo.com Bamenda, Cameroon   +237652249440(Phone)