Celso Campos Ricardo Quirós Joaquín Huerta Emilio Camahort Roberto Vivó Javier Lluch A Multiresolution Model for Non-photorealistic Rendering of Trees. 310-317 2006 conf/iccS/2006-2 International Conference on Computational Science (2) http://dx.doi.org/10.1007/11758525_41 db/conf/iccS/iccS2006-2.html#CamposQHCVL06