1. Arner, P., Quadratics as rational polynomials, Utah Math CAGD seminar, 1985.
2. Consurf I;Ball;Comput. Aided Design,1974
3. Consurf II;Ball;Comput. Aided Design,1975
4. Consurf III;Ball;Comput. Aided Design,1977
5. The parametric representation of curves and surfaces using rational polynomial functions;Ball,1987