Priebs, Axel, and Holger Gnest. “Spatial Planning in the Future: Requirements, Topics and Tasks from the Point of View of Planning Practices”. Raumforschung Und Raumordnung | Spatial Research and Planning, vol. 66, no. 6, Nov. 2008, pp. 486–497, https://doi.org/10.1007/BF03183149.