Johan Claes Koen Beets Frank Van Reeth A Corner-Cutting Scheme for Hexagonal Subdivision Surfaces. 13-20 2002 conf/smi/2002 Shape Modeling International http://csdl.computer.org/comp/proceedings/smi/2002/1546/00/15460013abs.htm db/conf/smi/smi2002.html#ClaesBR02