https://cel.archives-ouvertes.fr/cel-00963641 Contributor : Cimpa CimpaConnect in order to contact the contributor Submitted on : Friday, March 21, 2014 - 4:05:14 PM Last modification on : Monday, August 19, 2019 - 4:20:06 PM Long-term archiving on: : Saturday, June 21, 2014 - 12:01:19 PM