1. Ahmed, B. (2003). NASSD background paper: Sustainable tourism and cultural heritage (p. 49). IUCN, Northern Areas Programme.
2. Archer, B., & Cooper, C. (1998). The positive and negative impacts of tourism. In W. F. Theobald (Ed.), Global tourism (pp. 63–81). Butterworth-Heinemann.
3. Arshad, M. (2015). Making Lahore a better heritage tourist destination. Unpublished MSc Thesis. The Arctic University of Norway.
4. Association, A. T. T. (2010). Adventure tourism development index report 2010. Adventure Travel Trade Association/The George Washington University.
5. Ayres, R. (2000). Tourism as a passport to development in small states: Reflections on Cyprus. International Journal of Social Economics, 27, 114–133.