A. Scott,
« Power and people : aspects of micro-hydro »,
Waterlines, an international journal of water, sanitation and waste, p. p. 11-13: photogr., 1991.
M. W. Blokland, Boot, M. T., et van der Wildt, C. D.,
« Rada Water Supply and Sanitation Project Republic of Yemen : report of the fourth monitoring mission, 9-15 June 1991 ». Netherlands, Ministry of Foreign Affairs, DGIS, The Hague, The Netherlands, p. vii, 34 p., 1991.
T. Ramjeawon,
« Water systems and water management on the island of Mauritius », in
Population, economy, and environment in Mauritius : proceedings of a task force meeting held under the UNFPA sponsored project "Population and Sustainable Development: Mauritius" at IIASA, Laxenburg, Austria, 3-5 September 1990, 1991, p. P. 271-291: 9 fig., 6 tab.
R. Clarke,
Water : the international crisis. London, UK: Earthscan, 1991, p. xii, 193 p.: fig., tab.