J. M. Kalbermatten, Julius, D. S., Mara, D. D., and Gunnerson, C. G.,
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J. M. Kalbermatten, Julius, D. S., and Gunnerson, C. G.,
“Appropriate technology for water supply and sanitation : a sanitation field manual”, vol. no. 11. World Bank, Transportation, Water and Urban Development Department, Washington, DC, USA, p. iii, 86 p.: fig., tab., 1980.