Eric Berberich Arno Eigenwillig Michael Hemmer Susan Hert Kurt Mehlhorn Elmar Schömer A Computational Basis for Conic Arcs and Boolean Operations on Conic Polygons. 174-186 2002 conf/esa/2002 ESA http://link.springer.de/link/service/series/0558/bibs/2461/24610174.htm db/conf/esa/esa2002.html#BerberichEHHMS02