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On 2019-02-16 14:46, Eugene Podshivalov wrote:<br>
<blockquote type="cite"
cite="mid:CAEPw1JXEn3nyfakc9Ezuz29Lydqz6u3kW2_hv4VrA0tmyBseGQ@mail.gmail.com">Calculated
value may differ from the official one ...<br>
</blockquote>
<p>Official according to whom?</p>
<p>From <a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Nile#cite_note-length-1">https://en.wikipedia.org/wiki/Nile#cite_note-length-1</a> :</p>
<blockquote>
<p><i>"The length of the Nile is usually said to be about 6,650 km
(4,130 mi), but reported values lie anywhere between 5,499 km
(3,417 mi) and 7,088 km (4,404 mi). The length measurements of
many rivers are only approximations and differ from each other
because there are many factors that determine the calculated
river length, such as the position of the geographical source
and the mouth, the scale of measurement, and the length
measuring techniques"</i></p>
</blockquote>
<p>From <a class="moz-txt-link-freetext" href="https://en.wikipedia.org/wiki/Amazon_River">https://en.wikipedia.org/wiki/Amazon_River</a> :<br>
</p>
<blockquote>
<p>"<i>The Amazon River ... in South America is the largest river
by discharge volume of water in the world, and </i><i><b>by
some definitions</b></i><i> it is the longest.</i>" (<i>my
emphasis</i>)<br>
</p>
</blockquote>
<p>Encyclopedias are the preferred source for this kind of
information, not maps (or GIS databases).</p>
<p>Sergio</p>
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