 |
| coal- bearing: 26 phrases in 9 subjects |
| Coal | 4 |
| Geology | 5 |
| Geophysics | 1 |
| Makarov | 1 |
| Mining | 7 |
| Natural resourses and wildlife conservation | 1 |
| Oil / petroleum | 3 |
| Rail transport | 1 |
| Technology | 3 |
|
| coal- bearing: 26 phrases in 9 subjects |
| Coal | 4 |
| Geology | 5 |
| Geophysics | 1 |
| Makarov | 1 |
| Mining | 7 |
| Natural resourses and wildlife conservation | 1 |
| Oil / petroleum | 3 |
| Rail transport | 1 |
| Technology | 3 |