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ITU-T F.21
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ITU-T F.21
Composition of answer-back codes for the international gentex serviceMore info
This Recommendation describes the composition of answer-back codes for the international gentex service.
| Author | ITU |
|---|---|
| Editor | ITU |
| Document type | Standard |
| Format | File |
| ICS | 33.020 : Telecommunications in general
|
| Number of pages | 3 |
| Year | 1980 |
| Document history | |
| Country | Switzerland |
| Keyword | CCITT F.21;ITU-T 21;21;ITU-T F.21 |