https://hal.univ-rennes2.fr/hal-02292667 Contributor : Laurence LerouxConnect in order to contact the contributor Submitted on : Friday, September 20, 2019 - 9:47:30 AM Last modification on : Monday, December 13, 2021 - 12:02:14 PM Long-term archiving on: : Saturday, February 8, 2020 - 11:50:40 PM