https://cel.archives-ouvertes.fr/cel-01137317 Contributor : Jean-Marc GoglinConnect in order to contact the contributor Submitted on : Wednesday, April 1, 2015 - 10:57:36 AM Last modification on : Thursday, November 18, 2021 - 4:04:07 AM Long-term archiving on: : Thursday, July 2, 2015 - 9:31:31 AM