http://hal.in2p3.fr/in2p3-00020144 Contributor : Sylvie FloresConnect in order to contact the contributor Submitted on : Thursday, December 18, 2003 - 2:18:08 PM Last modification on : Friday, September 10, 2021 - 1:50:06 PM Long-term archiving on: : Tuesday, March 30, 2010 - 6:08:28 PM