| 17.1 |
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Automatic Identification System transmitter |
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| 17.2 |
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Automatic Identification System transmitter on floating marks (examples) |
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| 18.1 |
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Virtual Aid to Navigation with no known IALA-defined function |
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| 18.2 |
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Virtual Aid to Navigation with known IALA-defined function (example). The topmark indicates the navigational purpose, see Q130. Other carriers may be used. |
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