diff --git a/Kernel_23/doc/Kernel_23/CGAL/Kernel/global_functions.h b/Kernel_23/doc/Kernel_23/CGAL/Kernel/global_functions.h
index b26638c84b1..59823ac96c8 100644
--- a/Kernel_23/doc/Kernel_23/CGAL/Kernel/global_functions.h
+++ b/Kernel_23/doc/Kernel_23/CGAL/Kernel/global_functions.h
@@ -2688,12 +2688,14 @@ const CGAL::Point_3<Kernel>& r);
 
 // The same reason as do_intersect.
 
-/// \defgroup squared_distance_grp CGAL::squared_distance()
+/// \defgroup squared_length_grp CGAL::squared_distance()
 /// \ingroup kernel_global_function
 
 /// \defgroup squared_radius_grp CGAL::squared_length()
 /// \ingroup kernel_global_function
 
+/// @{
+
 /*!
 compute the squared length of vector `v`.
 */