Fix reference in FAQ

docs/faq.rst

@@ -148,7 +148,7 @@ that option under any normal circumstances.
 
 Note that checkpoints inside files are created only since version 1.1, 
 make sure you have an up-to-date version of borgbackup if you want to continue instead of retransferring a huge file.
-In some cases, there is only an outdated version shipped with your distribution (e.g. Debian). See :ref:`_installation`
+In some cases, there is only an outdated version shipped with your distribution (e.g. Debian). See :ref:`installation`.
 
 How can I backup huge file(s) over a unstable connection?
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