1. Dual Bézier curves and surfaces;Hoschek,1983
2. Envelope Curves and Surfaces;Sabin,1987
3. Implicit representation of parametric curves and surfaces;Sederberg;Comput. Vision Graph. Image Process,1984
4. Rational hodographs;Sederberg;Computer Aided Geometric Design,1987
5. Analytical Geometry of Three Dimensions;Sommerville,1951