https://hal-mines-paristech.archives-ouvertes.fr/hal-00647379 Contributor : Médard ThiryConnect in order to contact the contributor Submitted on : Thursday, December 1, 2011 - 10:13:56 PM Last modification on : Thursday, November 18, 2021 - 3:46:49 AM Long-term archiving on: : Friday, March 2, 2012 - 2:56:19 AM