L. Chairuca y Hassane, I.,
«Nitrate contamination in peri-urban Maputo (Mozambique)», in
Infrastructure, environment, water and people : proceedings of the 17th WEDC Conference, United Nations Centre for Human Settlement (Habitat), Nairobi, Kenya, 19-23 August 1991, 1991, pp. P. 203-207: 3 fig.
M. H. A. Wegelin-Schuringa,
«On-site sanitation : building on local practice», vol. no. 16-E. IRC, The Hague, The Netherlands, p. 74 p.: fig., tab., 1991.
J. E. M. Smet, Cairncross, S., Killewo, J. Z. J., Maikwano, L. F., y van Asten, H.,
«Patterns of hookworm and ascaris infection in Dar es Salaam»,
Acta tropica, pp. p. 247-249: tab., 1991.
B. Bradford y Brand, A.,
«Rainwater harvesting and water use in the barrios of Tegucigalpa». UNICEF, Tegucigalpa, Honduras, p. XI, 60 p.: 11 fig., 6 tab., ill., photogr., 1991.
E. O. Mairura y Nyangeri, G. E.,
«Site conditions in infrastructure development», in
Infrastructure for low-income communities : proceedings of the 16th WEDC conference : Regional Centre for Urban and Environmental Studies (RCUES), Osmania University, Hyderabad, India, 27-31 August, 1990, 1991, pp. P. 59-62: 3 fig.