Biblio

G. B. Gifford an Southampton and London, G. B. London Sch, “Evaluation of SWS filtration system”. Overseas Development Administration (ODA), London, UK, p. 251 p.: fig., tab., 1986.

D. M. Tam, Vigneswaran, S., and Visvanathan, C., Water filtration technologies for developing countries, vol. no. 12. Bangkok, Thailand: Environmental Sanitation Information Center, ENSIC, 1983, p. 110 p.: fig., tab.