diff --git a/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/is_pullout_direction_single_mold_translational_casting_2.h b/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/is_pullout_direction_single_mold_translational_casting_2.h
index 226dd236b2c..a8959abec93 100644
--- a/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/is_pullout_direction_single_mold_translational_casting_2.h
+++ b/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/is_pullout_direction_single_mold_translational_casting_2.h
@@ -11,6 +11,9 @@ namespace Set_movable_separability_2 {
  * colliding into the mold (but possibly sliding along the mold surface). It is
  * required that the polygon is <em>castable</em> this way.
  *
+ * The type that substitutes the template parameter `%CastingTraits_2` must be
+ * a model of the concept `CastingTraits_2`.
+ *
  * \param[in] pgn the input polygon.
  * \param[in] i the index of an edge in pgn.
  * \param[in] d the tested direction.
diff --git a/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/pullout_directions_single_mold_translational_casting_2.h b/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/pullout_directions_single_mold_translational_casting_2.h
index 0e4829e71b3..def1d501726 100644
--- a/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/pullout_directions_single_mold_translational_casting_2.h
+++ b/Set_movable_separability_2/doc/Set_movable_separability_2/CGAL/pullout_directions_single_mold_translational_casting_2.h
@@ -13,6 +13,9 @@ namespace Set_movable_separability_2 {
  * \f$y\f$-axis. In other words, every direction in the range (if exists) must
  * have a positive component in the positive \f$y\f$-direction.
  *
+ * The type that substitutes the template parameter `%CastingTraits_2` must be
+ * a model of the concept `CastingTraits_2`.
+ *
  * \param[in] pgn the input polygon.
  * \param[in] i the index of an edge in pgn.
  * \return a pair of elements, where the first is a Boolean that indicates