1. Die Landschaftsfresser;Krippendorf,1975
2. The Holiday-makers;Krippendorf,1987
3. Socio-economic development and ecological capacity in a mountainous region: a study of the Aletsch region (Switzerland);Messerli;Geographica Helvetica,1980
4. Mountain World in Danger;Nilsson,1991
5. The State of the World's Mountains: a Global Report,1992