1. Amery, H. A.: Water wars in the Middle East: a looming threat, The Geographical Journal, 168, 313–323, 2002.
2. Barnwell, T. O. and Johanson, R.: HSPF: A comprehensive package for simulation of watershed hydrology and water quality, in: Nonpoint Pollution Control: Tools and Techniques for the Future, Interstate Commission on the Potomac River Basin, Rockville, MD, 1981.
3. Carpenter, S. R., Mooney, H. A., Agard, J., Capistrano, D., DeFries, R. S., Díaz, S., Dietz, T., Duraiappah, A. K., Oteng-Yeboah, A., Pereira, H. M., Perrings, C., Reid, W. V., Sarukhan, J., Scholes, R. J., and Whyte, A.: Science for managing ecosystem services: Beyond the Millennium Ecosystem Assessment, Proc. Natl. Acad. Sci., 106, 1305–1312, https://doi.org/10.1073/pnas.0808772106, 2009.
4. Clark, W. C.: Sustainability science: a room of its own, Proc. Natl. Acad. Sci., 104, 1737–1738, 2007.
5. Dempster, C. E., Kock, J., and Mare, H. G.: Yield Analysis. March 2002. Report No. PB B100/00/0398 compiled by the BKS (Pty) Ltd / Jakoet & Associates / Wates, Meiring & Barnard (Pty) Ltd Consortium as part of the Development of an Integrated Water Resources Model of the Upper Olifants River (Loskop Dam) Catchment study for the Department of Water Affairs and Forestry, Directorate: Project Planning, Pretoria, South Africa, 2002.