Curves and surfaces in CAGD '89 : [proceedings of a conference held at the Mathematisches Forschungsinstitut Oberwolfach, F.R.G., 16-22 April 1989 / organized by R.E. Barnhill, W. Boehm, and J. Hoschek] ; edited by: R.E. Barnhill, W. Boehm, J. Hoschek
Papers presented at the 4th International Symposium "Surfaces in Computer Aided Geometric Design