1. UBFC, CNRS UMR 6249; OSU THETA; Besançon France
2. CNRS, IRD, IFSTTAR, ISTerre; Université Grenoble Alpes, Université Savoie Mont Blanc; Grenoble France
3. Helmholtz Centre Potsdam, Space Geodetic Techniques Section; GFZ German Research Centre for Geosciences; Potsdam Germany