Rallou Thomopoulos Jean-François Baget Ollivier Haemmerlé Conceptual Graphs as Cooperative Formalism to Build and Validate a Domain Expertise. 112-125 2007 conf/iccs/2007 ICCS http://dx.doi.org/10.1007/978-3-540-73681-3_9 db/conf/iccs/iccs2007.html#ThomopoulosBH07