| |||
| couche de fond; couche primaire; première couche | |||
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| couches basses; couches inférieures | |||
| English thesaurus | |||
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| Inside the Earth's atmosphere endoatmo-spheric up to an altitude of 35 km | |||
|
lower layer : 11 phrases in 3 subjects |
| Communications | 9 |
| Earth sciences | 1 |
| Telecommunications | 1 |