diff --git a/doc/muxers.texi b/doc/muxers.texi
index 070efff78c..f1774432f4 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -652,6 +652,11 @@ type @code{pcm} else type @code{tun} is set. @var{(default)}
 @end table
 @end table
 
+@section amr
+3GPP AMR (Adaptive Multi-Rate) audio muxer.
+
+It accepts a single audio stream containing an AMR NB stream.
+
 @anchor{asf}
 @section asf