Mayer, V. et al. 2001. Landscape as a soft locational factor: The development of guidelines, targets and project-based proposals for action to secure and develop aesthetic landscape qualities. Raumforschung und Raumordnung | Spatial Research and Planning. 59, 2-3 (Mar. 2001), 131–141. DOI:https://doi.org/10.1007/BF03184348.