Kama Nature Reserve. Photo: A. Tatnell, PCS Collection.
Water: 1
Vörösmarty CJ, Lévêque C & Revenga C (2005). Fresh water. In: Ecosystems and human well-being: current state and trends, vol 1, Hassan R, Scholes RJ & Ash N (eds), Island Press, Washington, DC, 165-208.