diff --git a/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Circular_kernel_2.h b/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Circular_kernel_2.h
index d0c1494c0d5..824bd036c2b 100644
--- a/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Circular_kernel_2.h
+++ b/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Circular_kernel_2.h
@@ -6,8 +6,7 @@ namespace CGAL {
 
 \models ::CircularKernel 
 
-Parameters 
--------------- 
+### Parameters ###
 
 The first parameter of the circular kernel must be instantiated with a 
 model of the `Kernel` concept. The `Circular_kernel_2` class 
diff --git a/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Line_arc_2.h b/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Line_arc_2.h
index 4abc6bdb9cb..6baada9491c 100644
--- a/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Line_arc_2.h
+++ b/Circular_kernel_2/doc/Circular_kernel_2/CGAL/Line_arc_2.h
@@ -6,8 +6,7 @@ namespace CGAL {
 
 \models ::CircularKernel::LineArc_2 
 
-I/O 
--------------- 
+### I/O ###
 
 The format for input/output is, for each line arc: a `Line_2` 
 (the supporting line) and two `Circular_arc_point_2` (the two endpoints),