4Th International Symp On Graph Theory And Combinatorics, Date: JUN, 1990, Location: MARSEILLE, FRANCE, Patrocinadores: FRENCH MATH SOC, CNRS, DIRECT RECH ETUDES & TECH, ELECT FRANCE, ECOLE NATL SUPER TELECOMMUN, INST NATL RECH INFORMAT & AUTOMAT, MAIRIE MARSEILLE, INT MATH UNION, PROGRAMME RECH COORDONNEE, MATH INFORMAT, Host: UNIV MARSEILLE LUMINY