Technology for water supply and sanitation in developing countries report of a WHO Study Group.
| Awdur Corfforaethol: | |
|---|---|
| Fformat: | Llyfr | 
| Iaith: | English | 
| Cyhoeddwyd: | Geneva
          World Health Organization
    
        1987. | 
| Cyfres: | Technical report series (World Health Organization)
              742. | 
| Pynciau: | 


