B. (Province) PK,
“Hand dug well improvement, traditional water storage and biological water quality”, vol. no. 1. Pakistan, Local Government & Rural Development Dept., Water & Sanitation Cell, Quetta, Pakistan, p. 16: 1 fig., 6 tab., 1994.
M. Chaudhuri, Gupta, A., and Verma, S. R.,
“Performance evaluation of ceramic filter candles”,
Journal of environmental engineering, pp. p. 1646-1651 : 2 fig., 1 tab., 1994.
M. Wegelin, Canonica, S., Mechsner, K., Fleischmann, T., Pesaro, F., and Metzler, A.,
“Solar water disinfection : scope of the process and analysis of radiation experiments”,
Aqua : journal of water supply research and technology, pp. p. 154-169 : 18 fig., 4 tab., 1994.