Dear friends, Attached you will find the slides I have used this morning for my presentation about WCC 2006 Best regards Ramon ========================================================================= Ramon Puigjaner Universitat de les Illes Balears Departament de Ciencies Matematiques i Informatica 07122 PALMA (Spain) Phone: +34-971173288 Fax: +34-971173003 e-mail: putxi@uib.es =========================================================================