David, C.-H. 2005. On the convergence of the National Spatial Planning Policies of France and Germany in the Post-EUREK process: The principle of subsidiarity in the debate on the European Constitutional Treaty and its impacts on the formation of a common spatial development policy. Raumforschung und Raumordnung | Spatial Research and Planning. 63, 1 (Jan. 2005), 11–20. DOI:https://doi.org/10.1007/BF03183452.