https://cel.archives-ouvertes.fr/in2p3-00012369 Contributor : Suzanne RobertConnect in order to contact the contributor Submitted on : Wednesday, December 11, 2002 - 11:32:32 AM Last modification on : Wednesday, September 16, 2020 - 4:02:25 PM Long-term archiving on: : Tuesday, March 30, 2010 - 5:45:45 PM