Colloquium Presentations   Geometric Modeling Using Hierarchical Refinement,  Computer Science Department,Purdue University, September 25, 1995 Curve Interpolation In Recursively Generated Surfaces Over Arbitrary Topology.  Department of Computer Science, Arizona State University, September, 1994. Mathematical Analysis of Recursively Generated Surfaces: Limit Points and LimitNormals, Department of Computer Science, Arizona State University, August 1993. B-spline Surfaces Over Irregular Meshes By Recursive Subdivision,  Department ofComputer Science, Arizona State University, August 1993. Polyhedral Subdivision Methods in Solid Modeling,  Department of OceanEngineering, MIT, September 1992. Recursively Generated Surfaces Over Polyhedral Meshes,  Department of OceanEngineering, MIT,  September 1992. Recursive Division in Free-Form Surfaces,  Fachbereich Mathematik und Informatik, University of Bremen,  Germany, 1989. Recursive Subdivision and Its Applications in Computer Graphics,  Natural Science  Division, Lebanese American University, November, 1997. Curve Interpolation in Computer-Aided Geometric Design,  Mathematics Department,AUB, 1995. Recursive Subdivision in Computer Aided Geometric Design,  Dept. ofMathematics, AUB, 1995. Recursive Subdivision Techniques in Computer Graphics,  UAE University, Dept. of Math. & Computer Science, 1989. Recursive Subdivision in Computer-Aided Geometric Design.  Faculty of Science Day, UAE University, 1988.