1. Daily, G. C. Nature's Services (Island Press, Washington, DC, 1997).
2. Millennium Ecosystem Assessment. Ecosystems and Human Well-Being: A Framework for the Assessment (Island Press, Washington, DC, 2003).
3. Hayward, B. From the Mountain to the Tap: How Land Use and Water Management Can Work for the Rural Poor (NR International, UK, 2005); available at
http://www.frp.uk.com/assets/Water_book.pdf
.
4. Gibbard, S., Caldeira, K., Bala, G., Phillips, T. J. & Wickett, M. Geophys. Res. Lett. 32, L23705 (2005).
5. Woodroffe, R., Thirgood, S. & Rabinowitz, A. (eds) People and Wildlife, Conflict or Co-existence? (Cambridge Univ. Press, New York, 2005).