First Author:   Hélène Laurent University of Namur, Namur, Belgium helene.laurent@unamur.be         Second Author: Marc Sangnier University of Namur, Namur, Belgium marc.sangnier@unamur.be         Third Author: Carole Treibich Univ. Grenoble Alpes, CNRS, INRAE, Grenoble INP, GAEL, Grenoble, France carole.treibich@univ-grenoble-alpes.fr