Biblio

World Meteorological Organization -Geneva, CH, WMO, “Comprehensive assessment of the freshwater resources of the world”. Stockholm Environment Institute (SEI), Stockholm, Sweden, p. v, 33 p. : 14 fig., photogr., tab., 1997.

World Meteorological Organization -Geneva, CH, WMO and Paris, F. R. U. N. E. S. C. O. -, The world's water : is there enough?, vol. no. 857. Geneva, Switzerland: World Meteorological Organization, 1997, p. 22 p. : 6 fig.;.