1. LAGA, UMR CNRS 7539, Université Paris XIII, Villetaneuse, France; INRIA, ANGE Project-Team, Rocquencourt, Le Chesnay, France; CEREMA, ANGE Project-Team, Margny-Lès-Compiègne, France; and LJLL, ANGE Project-Team, UPMC Université Paris VI, Paris, France
2. LMV, UMR CNRS 8100, Universit´e de Versailles-Saint-Quentin-en-Yvelines, Versailles, France
3. MAPMO, UMR CNRS 7349, Université d’Orléans, France; INRIA, ANGE Project-Team, Rocquencourt, Le Chesnay, France; CEREMA, ANGE Project-Team, Margny-Lès-Compiègne, France; and LJLL, ANGE Project-Team, UPMC Université Paris, France