http://hal.in2p3.fr/in2p3-00023171 Contributor : Suzanne RobertConnect in order to contact the contributor Submitted on : Tuesday, October 12, 2004 - 10:19:21 AM Last modification on : Wednesday, September 16, 2020 - 4:07:25 PM Long-term archiving on: : Thursday, April 1, 2010 - 3:16:26 PM