diff --git a/doc/nut.texi b/doc/nut.texi
index dafbb392e7..9de9521635 100644
--- a/doc/nut.texi
+++ b/doc/nut.texi
@@ -17,6 +17,10 @@ subtitle and user-defined streams in a simple, yet efficient, way.
 It was created by a group of FFmpeg and MPlayer developers in 2003
 and was finalized in 2008.
 
+The official nut specification is at svn://svn.mplayerhq.hu/nut
+In case of any differences between this text and the official specification,
+the official specification shall prevail.
+
 @chapter Container-specific codec tags
 
 @section Generic raw YUVA formats