1. ASPRS (American Society for Photogrammetry and Remote Sensing): 2004, Common definitions and terms. (http://www.asprs.org/asprs/news/Forecast_Definitions.htm, accessed 3 January 2005).
2. Avery, T. E.: 1968, Interpretation of Aerial Photographs 2nd ed. Burgess Publishing Co., Minneapolis, Minnesota. pp. 37–38.
3. Booth, D. T., Glenn, D., Keating, B., Cox, S. E., Nance, J. and Barriere, J. P.: 2004, ‘Monitoring Rangelands with Very-large Scale Aerial Imagery’, in: Proceedings 19th Biennial Workshop on Color Photography, Videography and Airborne Imaging for Resource Assessment. October 6–8, 2003, Logan, Utah. Published on CD by American Society for Photogrammetry and Remote Sensing, Bethesda, Maryland.
4. Booth, D. T., Glenn, D., Keating, B., Nance, J., Cox, S. E. and Barriere, J. P.: 2003, ‘Monitoring Rangeland Watersheds with Very-large Scale Aerial Imagery’, in: Kenneth G. Renard et al. (comps.), Proceedings of the First Interagency Conference on Research in the Watersheds’, October 27–30, 2003, Benson, Arizona, pp 212–215. Washington, D. C: USDA Agricultural Research Service.
5. Comer, R. P., Kinn, G., Light, D. and Mondello, C.: 1998, ‘Talking digital’, Photogrammetric Eng. Remote Sens. 64, 1139–1142.