Fixed mismatching title overline.
diff --git a/Doc/tutorial/stdlib2.rst b/Doc/tutorial/stdlib2.rst
index 2d11d55..22c2a4f 100644
--- a/Doc/tutorial/stdlib2.rst
+++ b/Doc/tutorial/stdlib2.rst
@@ -1,6 +1,6 @@
 .. _tut-brieftourtwo:
 
-*********************************************
+**********************************************
 Brief Tour of the Standard Library --- Part II
 **********************************************