TY  - BOOK
AU  - Mann, H. T
AU  - Williamson, D
AU  - Intermediate Technology Development Group
TI  - Water treatment and sanitation: a handbook of simpple methods for rural areas in developing countries 
AV  - TD 430 I84
PY  - 1973///
CY  - London
PB  - [s.n.]
KW  - Purificación del agua
ER  -