==Key documents==
Fonseca, C., Dubé, A. and Verhoeven, J., 2011. [http://www.washcost.info/page/1473 Cost-based decision support tools for water and sanitation]. (WASHCost working paper 4). The Hague, The Netherlands: IRC International Water and Sanitation Centre.
Tandon* Fonseca, PC., Dubé, A. and PizarroVerhoeven, GJ., 20062011. [http://www. washcost.info/page/1473 Cost-based decision support tools for water and sanitation]. (WASHCost working paper 4). The Hague, The Netherlands: IRC International Water and Sanitation Needs Assessment Tool for use in assessing national needs to achieve the MDGsCentre. New York, NY, USA: UN Millennium Project, United Nations Development Programme (UNDP)
* Tandon, P. and Pizarro, G., 2006. Water and Sanitation Needs Assessment Tool for use in assessing national needs to achieve the MDGs. New York, NY, USA: UN Millennium Project, United Nations Development Programme (UNDP) * Wiemers, A., 2005. [http://content.undp.org/go/cms-service/stream/asset/;jsessionid=aIHA9xSEGS69?asset_id=2548671 Water and Sanitation Needs Assessment Model user guide]. (MDG Needs Assessment Tools). New York, NY, USA: UN Millennium Project, United Nations Development Programme (UNDP)