diff --git a/reference/cairo/book.xml b/reference/cairo/book.xml
index ac6c613d24..961ade1422 100644
--- a/reference/cairo/book.xml
+++ b/reference/cairo/book.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
-<!-- $Revision: $ -->
+<!-- $Revision$ -->
 
 <book xml:id="book.cairo" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  <title>Cairo</title>