Biblio

C. H. A. G. U. A. S. A. N. - S. Gallen y Gallen, C. H. S. K. A. T. - St., «Sustainability of drinking water supply and sanitation projects : report on the 6th AGUASAN workshop : Gersau (July 2 to 6, 1990) : summary». SKAT (Swiss Centre for Development Cooperation in Technology and Management), St. Gallen, Switzerland, p. 7 p., 1990.