https://cel.archives-ouvertes.fr/cel-00339201 Contributor : Daniel QuemadaConnect in order to contact the contributor Submitted on : Thursday, December 11, 2008 - 4:03:36 PM Last modification on : Thursday, March 4, 2021 - 4:21:47 PM Long-term archiving on: : Monday, June 7, 2010 - 8:02:06 PM