Concepts for national assessment of water availability and use report to Congress.
| Fformat: | Llyfr | 
|---|---|
| Iaith: | English | 
| Cyhoeddwyd: | Reston, Va.
          U.S. Geological Survey
    
        2002. | 
| Cyfres: | U.S. Geological Survey circular
              1223 | 
| Pynciau: | 


