Steven Willmott Monique Calisti Boi Faltings Santiago Macho-Gonzalez Omar Belakhdar Marc Torrens CCL: Expressions of Choice in Agent Communication. 325-332 2000 conf/icmas/2000 ICMAS http://doi.ieeecomputersociety.org/10.1109/ICMAS.2000.858470 db/conf/icmas/icmas2000.html#WillmottCFMBT00