Greg Garvey Brenda Laurel Rob Tow Joan I. Staveley Allucquère Rosanne Stone Grids, guys and gals: are you oppressed by the Cartesian coordinate system? (panel session). 503-505 1995 SIGGRAPH http://doi.acm.org/10.1145/218380.218536 db/conf/siggraph/siggraph1995.html#GarveyLTSS95