Funding for this research was provided by:
Jean Frederic Myoupo
Text and Data Mining valid from 2018-07-02
Received: 13 October 2017
Accepted: 25 April 2018
First Online: 2 July 2018
: VKT and YFY are with the department of Mathematics and Computer Science of the University of Dschang, Cameroon. JFM is with the Computer Science Lab. MIS of the university of Picardie Jules Verne, Amiens, France.
: The authors declare that they have no competing interests.
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