https://cel.archives-ouvertes.fr/hal-02942054 Contributor : Bruno GrenetConnect in order to contact the contributor Submitted on : Thursday, September 17, 2020 - 3:17:29 PM Last modification on : Wednesday, November 3, 2021 - 7:45:20 AM Long-term archiving on: : Thursday, December 3, 2020 - 10:00:23 AM