G. Smethurst,
Basic water treatment for application world-wide, 2nd ed.nd ed. London, UK: Thomas Telford, 1988, p. 216 p.: fig., tab.
K. E. I. N. F. O. T. E. R. R. A. Nairobi,
Fire, wood, water : reaping the benefits, vol. no. 1. Nairobi, Kenya: UNEP, United Nations Environment Programme, 1988, p. x, 119 p.: fig., tab.
P. J. G.,
“Saneamiento basico rural en Uraba”,
Revista Ainsa, pp. p. 55-72: fig., 1988.
VITA -Arlington, VA, US,
Village technology handbook. Arlington, VA, USA: Volunteers in Technical Assistance, 1988, p. xiv, 422 p. : fig.