diff --git a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/Arrangement_on_surface_2.txt b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/Arrangement_on_surface_2.txt
index cd3d3328c77..0287ab3226c 100644
--- a/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/Arrangement_on_surface_2.txt
+++ b/Arrangement_on_surface_2/doc/Arrangement_on_surface_2/Arrangement_on_surface_2.txt
@@ -3575,7 +3575,7 @@ The concept `AosApproximateTraits_2` refines the concept
 `Approximate_number_type` required by the latter, a model of the
 `AosApproximateTraits_2` concept must define the type
 `Approximate_point_2`, which is typically defined as
-`CGAL::Cartesian<Approximate_number_type>::Point_2`. Also, it must
+`CGAL::Cartesian<Approximate_number_type>::%Point_2`. Also, it must
 support the operations below (in addition to the operation required by
 the concept `AosApproximatePointTraits_2`).