Chike Obi (April 17, 1921 – March 13, 2008) was a Nigerian politician, mathematician and professor.The African Mathematics Union suggests that he was the first Nigerian to hold a doctorate in mathematics. Dr. Obi's early research dealt mainly with the question of the existence of periodic solutions of non-linear ordinary differential equations. He successfully used the perturbation technique, and several of his publications greatly helped to stimulate research interest in this subject throughout the world and have become classics in the literature. Wikipedia
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