G. Hutton, Pfeiffer, V., Blume, S., Muench, E., Malz, Y., et Sustainable Sanitation Alliance -Eschborn, DE, SuSanA,
« Costs and economics of sustainable sanitation ». Sustainable Sanitation Alliance, SuSanA, Eschborn, Germany, p. 8 p. : 3 fig., 4 photogr., 1 tab., 2009.