A. Potter, Klutse, A., Snehalatha, M., Batchelor, C., Uandela, A., Naafs, A., Fonseca, C., y Moriarty, P. B.,
«Assessing sanitation service levels»,
WASHCost global working papers, vol. 3. IRC, The Hague, The Netherlands, p. 27 p. : 16 fig., 2011.
A. Potter,
«Assessing sanitation service levels : a new approach»,
Sanitation matters: a magazine for Southern Africa, pp. p. 18 - 19 : ill., 2011.