https://hal-sfo.ccsd.cnrs.fr/sfo-00658676 Contributor : Saïda GuellatiConnect in order to contact the contributor Submitted on : Tuesday, January 10, 2012 - 10:15:43 PM Last modification on : Sunday, June 26, 2022 - 2:18:32 AM Long-term archiving on: : Wednesday, April 11, 2012 - 2:35:25 AM