R.F. Tobler, S. Maierhofer, A Wilkie:
"A Multiresolution Mesh Generation Approach for Procedural Definition of Complex Geometry";
in: "Shape Modelling International 2002", IEEE Computer Society, 2002, ISBN: 0-7695-1546-0, 35 - 42.
http://publik.tuwien.ac.at/files/PubDat_137265.pdf