| |||
lage frequentie | |||
lage frequente |
baja frecuencia : 38 phrases in 10 subjects |
Automated equipment | 1 |
Communications | 12 |
Earth sciences | 3 |
Electronics | 14 |
Environment | 1 |
Information technology | 2 |
Mechanic engineering | 1 |
Medical | 2 |
Metallurgy | 1 |
Transport | 1 |