P. B. Moriarty, Batchelor, C., Fonseca, C., Klutse, A., Naafs, A., Nyarko, K., Pezon, C., Potter, A., Reddy, R., et Snehalatha, M.,
« Ladders for assessing and costing water service delivery »,
WASHCost global working papers, vol. 2. IRC , The Hague, the Netherlands, p. iv, 19 p. : 5 fig., 5 tab., 2011.
