Becher, E.

Becher, E., Shipman, H.R. & Bierstein, P.S., 1985. A review of the WHO/World Bank cooperative programme in community water supply and sanitation (1971-1984), Geneva, Switzerland: World Health Organization, Community Water Supply & Sanitation Unit. Available at: https://es.ircwash.org/sites/default/files/202.5-85RE-5959.pdf.