L. K. National W. Ratmalana,
Ground water, vol. no. D4. Ratmalana, Sri Lanka: National Water Supply and Drainage Board, 1988, p. ii, 53 p.: fig.
IDRC -Ottawa, Ont., CA, International Development Research Centre y IRC International Water and Sanitation Centre, The Hague, NL,
Handpumps : issues and concepts in rural water supply programmes, vol. no. 25. The Hague, The Netherlands: IRC, 1988, p. xi, 163 p.: fig., tab.
R. Stark,
«Well construction manual». Sarvodaya Rural Technical Services, Moratuwa, Sri Lanka, p. 26 p.: fig., 1988.