Franck Favetta Marie-Aude Aufaure-Portier About Ambiguities in Visual GIS Query Languages: A Taxonomy and Solutions. 154-165 http://link.springer.de/link/service/series/0558/bibs/1929/19290154.htm 2000 conf/visual/2000 VISUAL db/conf/visual/visual2000.html#FavettaA00