• An Annual Conference of the Society for Mathematical Biology Joint with Japan Association for Mathematical Biology, 16-19 July 2001, Hilo, Hawaii
  • Sixth SIAM Conference on Applications of Dynamical Systems, 20-24 May 2001, Snowbird Ski and Summer Resort, Snowbird, Utah
  • Joint Conference of the American Mathematical Society and the Mathematical Association of America, 10-13 January, 2001, New Orleans, Louisiana
  • “An optimal control problem in population dynamics”, Mathematical Biology Seminar, Arizona State University, spring 1998
  • “Complex numbers and some of their applications”, First Annual Conference of Cameroonian Mathematicians Union in the Soviet Union, July 8-10, 1990, Ivanova, Russian Federation, USSR
  • “Parabolic boundary value problems in an infinite band”, Second Annual Conference of Cameroonian Mathematicians Union Joint with Cameroonian Physicists in the Soviet Union, May 8-10, 1991, Kharkov, Ukraine, USSR
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