K. R. Bulusu and Nawlakhe, W. G.,
“Defluoridation”. National Environmental Engineering Research Institute, NEERI, Nagpur, India, p. viii, 61 p., [7] p. pl.: 8 fig., 18 tab., 1992.
M. Chaudhuri and Gupta, A.,
“Domestic water purification for developing countries”,
Aqua : journal of water supply research and technology, pp. p. 290-298: 8 fig., 5 tab., 1992.
R. M. Clark, Adams, J. Q., Goodrich, J. A., and Lykins, B. W.,
“Safe drinking water from small systems : treatment options”,
Journal American Water Works Association, pp. p. 49-55: 4 fig., 6 tab., photogr., 1992.