eau de traitement: 47 phrases in 13 subjects |
Agriculture | 1 |
Chemistry | 2 |
Economy | 1 |
Environment | 26 |
General | 2 |
Mechanic engineering | 1 |
Name of organization | 1 |
Patents | 1 |
Politics | 1 |
Textile industry | 2 |
United Nations | 2 |
Waste management | 2 |
Water resources | 5 |