 |
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| метод Фраша (a method to extract sulfur from underground deposits MichaelBurov) | |||
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Frasch process : 2 phrases in 1 subject |
| Technology | 2 |
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| метод Фраша (a method to extract sulfur from underground deposits MichaelBurov) | |||
|
Frasch process : 2 phrases in 1 subject |
| Technology | 2 |