https://hal-upec-upem.archives-ouvertes.fr/hal-00619216 Contributor : Marie-Pierre BéalConnect in order to contact the contributor Submitted on : Monday, September 5, 2011 - 6:00:31 PM Last modification on : Saturday, January 15, 2022 - 3:59:28 AM Long-term archiving on: : Tuesday, December 6, 2011 - 2:28:26 AM