https://cel.archives-ouvertes.fr/cel-00331921 Contributor : Maurice Robert KiblerConnect in order to contact the contributor Submitted on : Friday, September 5, 2014 - 10:33:34 AM Last modification on : Friday, September 10, 2021 - 1:50:13 PM Long-term archiving on: : Saturday, December 6, 2014 - 10:58:08 AM