A curve is simple if it does not cross itself.
Wolfram MathWorld - Murat Alper
Simple Curve -- from Wolfram MathWorld
graphics - How to create a new person curve? - Mathematica Stack Exchange
Epicycloid - Wikipedia
Sphere-Sphere Intersection - From Wolfram MathWorld, PDF, Sphere
Surface Of Constant Width, curve Of Constant Width, franz Reuleaux, Curvilinear, Reuleaux triangle, Asymptote, wolfram Research, mathworld, curve, shape
Math conflicts - Z006 - Herb Zinser's Science WAR analysis reports
multigraph in discrete mathematics –
2. Art Gallery Theorem
Symbolizing Collective Remembering Otherwise
Superellipse -- from Wolfram MathWorld Mathematical shapes, Geometric transformations, Logarithmic spiral
Curve Article about curve by The Free Dictionary
Knot Theory