INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr|INRIA Rocquencourt, BANG project team, Le Chesnay Cedex, France. annabelle.ballesta@inria.fr