diff --git a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/PolylineNode_concept.h b/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/PolylineNode_concept.h
deleted file mode 100644
index 62ddebe9869..00000000000
--- a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/PolylineNode_concept.h
+++ /dev/null
@@ -1,22 +0,0 @@
-/// This classcept represent s wrap per are passed to the polyline simplification algorithm to calculate
-/// the "cost" of removing a vertex. Such a cost represents some measure of the deviation error between the
-/// polyline sets before and after removal. The smaller the error the lower the cost, and the algoritm processes
-/// vertices in increasing cost order to preserve the overall polyline set shape as much as possible
-/// concept
-class PolylineSimplificationNode
-{
-  
-public:
-
-  /// Returns the cost
-  template<class Tr, class VertexDescriptor, class PointIterator>  
-  boost::optional<double> operator()( Tr               const& aTr      
-                                    , VertexDescriptor const& aPV
-                                    , VertexDescriptor const& aQV
-                                    , VertexDescriptor const& aRV
-                                    , PointIterator           aOriginalSubpolyline_VerticesBegin
-                                    , PointIterator           aOriginalSubpolyline_VerticesEnd
-                                    ) const ;
-  
-};
-
diff --git a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Vertex_concept.h b/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Vertex_concept.h
deleted file mode 100644
index c08fe2e2462..00000000000
--- a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Vertex_concept.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/// An implementation-defined model of this concept is the vertex of the 2D constrained Delaunay triangulation that is used internally
-/// by the polyline simplification data structure.
-struct PolylineSimplificationVertex : CGAL::Triangulation_vertex_base_with_id_2
-{
-    /// @return true if this vertex correspond to an endpoint of an open polyline
-    bool is_terminal() const ;
-
-    /// @return Sets whether the vertex is terminal or not.
-    void set_is_terminal( bool is ) ;
-
-    /// @return true if this vertex is shared by more than one polyline
-    bool is_shared() const ;
-
-    /// @return Sets whether the vertex is shared or not.
-    void set_is_shared( bool is ) ;
-
-    /// @return true if this vertex has been manually marked as fixed by the user
-    bool is_fixed() const ;
-
-    /// @return Sets whether the vertex is fixed or not.
-    void set_is_fixed( bool is );
-    
-    /// @return The simplification cost for the vertex as computed by the 'PolylineSimplificationCostFunction'
-    boost::optional<double> cost() const ;
-  
-};
-
diff --git a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Visitor_concept.h b/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Visitor_concept.h
deleted file mode 100644
index 79bfbf786dc..00000000000
--- a/Polyline_simplification_2/include/CGAL/Polyline_simplification_2/reference_manual_concepts/Visitor_concept.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/// Modles of this concept represent a visitation function object whose methods are called at key steps during
-/// the simplification process.
-struct PolylineSimplificationVisitor
-{
-  /// Called at the very beggining, before vertices are being collected for processing
-  void OnStarted() const {} 
-  
-  /// Called at the very end when the simplification finished
-  void OnFinished() const {} 
-  
-  /// Called when the 'PolylineSimplificationStopPredicate' returned true
-  void OnStopConditionReached() const {} 
-  
-  /// Called when a vertex that has been alreay classified as "removable" is put in the processing queue.
-  /// @param vertex the collected vertex (as a 'PolylineSimplificationVertex')
-  template<class VertexHandle>
-  void OnCollected( VertexHandle const& vertex ) const {}                
-  
-  /// Called when a vertex has been popped off the processing queue and will be removed
-  /// @param vertex the processed vertex
-  /// @param cost   the cost of removing the current vertex as calculated by the 'PolylineSimplificationCostFunction'
-  /// @param initial_count the initial total number of vertices in the polyline set
-  /// @param current_count the current total number of vertices in the polyline set
-  template<class VertexHandle>
-  void OnSelected( VertexHandle const& vertex, boost::optional<double> const& cost, unsigned initial_count, unsigned current_count) const {}                
-  
-  /// Called just before a selected vertex is removed
-  /// @param p the previous vertex along the polyline
-  /// @param q the vetex about to be remove
-  /// @param r the next vertex along the polyline
-  template<class VertexHandle>
-  void OnRemoving( VertexHandle const& p, VertexHandle const& q, VertexHandle const& r) const {}          
-  
-  /// Called right after a selected vertex has been removed
-  /// @param p the remaning vertex along the polyline that was right before "q" (now removed)
-  /// @param r the remaning vertex along the polyline that was right after  "q" (now removed)
-  template<class VertexHandle>
-  void OnRemoved( VertexHandle const& p, VertexHandle const& r) const {}        
-  
-  /// Called when a vertex that has been classified as "non-removable"
-  /// @param vertex the non-removable vertex 
-  template<class VertexHandle>
-  void OnNonRemovable( VertexHandle const& vertex) const {}                
-
-};