An isolated singularity of a function is a singularity at a point at which the surface is not differentiable and with no other singularity in a sufficiently small enough neighborhood of . Different types of singularities have been studied and classified; see .
 GALAAD Project Team. "Classification of Isolated Singularities." (Sept 30, 2013) www-sop.inria.fr/galaad/surface/classification.
 S. Holzer and O. Labs, "Illustrating the Classification of Real Cubic Surfaces," Algebraic Geometry and Geometric Modeling, Mathematics and Visualization, Berling: Springer, 2006 pp. 119–134.
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Published: October 15 2013