http://hal.in2p3.fr/in2p3-00020243 Contributor : Jocelyne LorgerilConnect in order to contact the contributor Submitted on : Thursday, January 15, 2004 - 3:06:10 PM Last modification on : Wednesday, September 16, 2020 - 4:06:57 PM Long-term archiving on: : Tuesday, March 30, 2010 - 6:13:36 PM