1. Université de Lorraine, CNRS, CRAN, F-54000 Nancy, France
2. Sorbonne Université, CNRS, Université de Paris, Inria, Laboratoire Jacques-Louis Lions (LJLL), F-75005 Paris, France
3. Chair in Applied Analysis, Alexander von Humboldt-Professorship, Department of Mathematics, Friedrich-Alexander-Universiät Erlangen-Nürnberg, 91058 Erlangen, Germany
4. Chair of Computational Mathematics, Fundación Deusto, University of Deusto, 48007 Bilbao, Basque Country, Spain
5. Departamento de Matematicas, Universidad Autonoma de Madrid, 28049 Madrid, Spain