 |
| |||
| coal and oil combustion | |||
| charbon en suspension: 2 phrases in 2 subjects |
| Environment | 1 |
| Natural resourses and wildlife conservation | 1 |
|
| |||
| coal and oil combustion | |||
| charbon en suspension: 2 phrases in 2 subjects |
| Environment | 1 |
| Natural resourses and wildlife conservation | 1 |