1. Aitken, R., Watson, R. D., & Greene, D. (1992). Wild land in Scotland – A review of the concept, unpublished report.
2. Indicators of wildness: Using attributes of the land to assess the context of wilderness;Aplet,2000
3. Determination of thresholds of visual impact: The case of wind turbines;Bishop;Environment and Planning B,2002
4. Tourism in the cairngorms national park;Cairngorms National Park Authority,2006
5. Mapping the wilderness continuum using raster GIS;Carver,1996