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Solsona, F. and Kariuki, A.W., Report to the Water Research Commission. Part 1 on a dynamic cross-flow sand filter for rural water treatment. Part 2 on a technical guide for a dynamic cross-flow sand filter, vol. no. 539/1/97. Pretoria, South Africa: Water Research Commission, WRC, 1997, p. vii, 77 p. : fig., photogr., tab.

Visscher, J.T., Latorre M., J., and Galvis C., G., “Performance evaluation of dynamic roughing filtration”, in Advances in slow sand and alternative biological filtration, 1996, pp. P. 349-358 : 5 fig., 3 tab.

Wegelin, M., Zimmerman, T., and Burgthaler, B., “Rehabilitation of slow sand filters and new treatment plant designs in rural Cameroon”, in Advances in slow sand and alternative biological filtration, 1996, pp. P. 359-369 : 7 fig., 5 tab.

Lloyd, B.J., Visscher, J.T., and Galvis C., G., “Overcoming water quality limitations with the multi-barrier concept : a case study from Colombia”, in Slow sand filtration : an international compilation of recent scientific and operational developments, 1994, pp. P. 47-60: fig., 3 tab.

Latorre M., J., “Performance evaluation of dynamic roughing filtration”, vol. no. 137. IHE (International Institute for Infrastructural, Hydraulic and Environmental Engineering), Delft, The Netherlands, p. vi, 83 p.: 30 fig., 11 tab., 1994.

Quiroga R., E., “A successful water rehabilitation project arising from diagnostic surveillance”. University of Surrey, Department of Civil Engineering, Guildford, UK, p. viii, 75 p.: 18 fig., 7 tab., 1994.

Galvis C., G., “Tecnologia innovativa para reduccion de contaminantes biologicos y precursores de trihalometanos”, Gaceta ambiental, pp. p. 5-13: 8 fig., 3 tab., 1994.

Visscher, J.T., Galvis C., G., and Fernandez, J., “Comparative study of different pre-treatment alternatives”, Aqua : journal of water supply research and technology, pp. p. 337-346: 7 fig., 5 tab., 1993.

Galvis C., G., “Innovative technology for reduction in biological contaminants and trihalomethane precursors”, in Safety of water disinfection : balancing chemical and microbial risks, 1993, pp. P. 415-428: 10 fig., 3 tab.

Visscher, J.T., Beron, F., Galvis C., G., and Fernandez, J., “Pre-treatment alternatives for drinking water supply systems : selection, design, operation and maintenance”, vol. no. 22. IRC, The Hague, The Netherlands, p. viii, 101 p.: 40 fig., 19 tab., 1993.

CINARA -Cali, CO and IRC International Water and Sanitation Centre, The Hague, NL, “Proyecto integrado de investigacion y demostracion de metodos de pretratemiento para sistemas de abastecimiento de agua : informe final : desarrollo, logros y perspectivas”. IRC, The Hague, The Netherlands, p. xxix, 233 p.: 52 fig., 47 tab., 1992.