 |
| highly-concentrated: 6 phrases in 6 subjects |
| Astronautics | 1 |
| Aviation | 1 |
| Makarov | 1 |
| Nanotechnology | 1 |
| Natural resourses and wildlife conservation | 1 |
| Nuclear and fusion power | 1 |
|
| highly-concentrated: 6 phrases in 6 subjects |
| Astronautics | 1 |
| Aviation | 1 |
| Makarov | 1 |
| Nanotechnology | 1 |
| Natural resourses and wildlife conservation | 1 |
| Nuclear and fusion power | 1 |