https://hal-lara.archives-ouvertes.fr/hal-02101267 Contributor : Colette ORANGEConnect in order to contact the contributor Submitted on : Tuesday, April 16, 2019 - 3:54:15 PM Last modification on : Wednesday, April 17, 2019 - 1:26:42 AM Long-term archiving on: : Wednesday, July 17, 2019 - 2:41:08 PM