Dac-Huy Tran Philippe Baptiste Vu Duong From Sets to Geometrical Sectors in the Airspace Sectorization Problem. 7-10 2004 conf/rivf/2004 RIVF http://e-ifi.org/rivf/2004/proceedings/ArticlesRIVR_04/p07-10.pdf db/conf/rivf/rivf2004.html#TranBD04