diff --git a/Doc/library/email.header.rst b/Doc/library/email.header.rst
index 80c7346..c385cf3 100644
--- a/Doc/library/email.header.rst
+++ b/Doc/library/email.header.rst
@@ -119,7 +119,7 @@
       which they appear in the string.  Space and tab may be included in the
       string to indicate whether preference should be given to one over the
       other as a split point when other split chars do not appear in the line
-      being split.  Splitchars does not affect RFC 2047 encoded lines.
+      being split.  Splitchars does not affect :RFC:`2047` encoded lines.
 
       *maxlinelen*, if given, overrides the instance's value for the maximum
       line length.