Rémi Allègre Aurélien Barbier Eric Galin Samir Akkouche A Hybrid Shape Representation for Free-Form Modelling (Figures 7, 9, and 10). 385 2004 conf/smi/2004 SMI http://csdl.computer.org/comp/proceedings/smi/2004/2075/00/20750385.pdf db/conf/smi/smi2004.html#AllegreBGA04a