Eßer, Anke, and David Schmedding. “Tradeable Permits As a Steering Instrument for Goods Traffic in Ecologically Sensitive Areas: The Case of the Brenner Motorway”. Raumforschung Und Raumordnung | Spatial Research and Planning, vol. 63, no. 6, Nov. 2005, pp. 400–411, https://doi.org/10.1007/BF03182969.