diff --git a/Linear_cell_complex/examples/Linear_cell_complex/CMakeLists.txt b/Linear_cell_complex/examples/Linear_cell_complex/CMakeLists.txt
index 7ded1d579a6..390519eb032 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/CMakeLists.txt
+++ b/Linear_cell_complex/examples/Linear_cell_complex/CMakeLists.txt
@@ -11,8 +11,8 @@ endif()
 # If you want to visualize a linear cell complex, you can use the following viewer
 # based on qt. Just uncomment the following two lines, plus the lines qt5_use_modules below
 
-#find_package(CGAL COMPONENTS Qt5)
-#include("CMakeLCCViewerQt.inc")
+# find_package(CGAL COMPONENTS Qt5)
+# include("CMakeLCCViewerQt.inc")
 
 # If you don't want to visualize, use the following line (otherwise comment it)
 find_package(CGAL QUIET COMPONENTS Core)
@@ -40,13 +40,6 @@ if ( CGAL_FOUND )
   create_single_source_cgal_program("plane_graph_to_lcc_2.cpp")
   create_single_source_cgal_program("linear_cell_complex_3_attributes_management.cpp")
 
-  add_executable(linear_cell_complex_3_triangulation
-                          linear_cell_complex_3_triangulation.cpp)
-  target_link_libraries(linear_cell_complex_3_triangulation ${CGAL_LIBRARIES}
-                                   ${CGAL_3RD_PARTY_LIBRARIES}
-                                   ${MAP_VIEWER_LIBRARIES})
-  # qt5_use_modules(linear_cell_complex_3_triangulation ${MAP_VIEWER_MODULES})
-
   add_executable(voronoi_2 voronoi_2.cpp)
   target_link_libraries(voronoi_2 ${CGAL_LIBRARIES} ${CGAL_3RD_PARTY_LIBRARIES}
                                   ${MAP_VIEWER_LIBRARIES})
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/README.txt b/Linear_cell_complex/examples/Linear_cell_complex/README.txt
index 4001f29b2e1..6326da0e665 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/README.txt
+++ b/Linear_cell_complex/examples/Linear_cell_complex/README.txt
@@ -13,12 +13,6 @@ Examples for Linear_cell_complex package:
   Program allowing to transform a planar graph into a 2D linear cell complex.
 
 
-* linear_cell_complex_3_triangulation.cpp
-
-  Example showing how to triangulate a face of a Linear_cell_complex, 
-  using CGAL::Constrained_Delaunay_triangulation_2.
-
-
 * voronoi_2.cpp
 
   Example showing how to compute 2D voronoi diagram of a set of 2D points.
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_triangulation.cpp b/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_triangulation.cpp
deleted file mode 100644
index 38abbf0c246..00000000000
--- a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_triangulation.cpp
+++ /dev/null
@@ -1,272 +0,0 @@
-#include <CGAL/Linear_cell_complex.h>
-#include <CGAL/Linear_cell_complex_constructors.h>
-#include <CGAL/Linear_cell_complex_operations.h>
-
-#include <CGAL/Triangulation_2_filtered_projection_traits_3.h>
-#include <CGAL/Triangulation_vertex_base_with_info_2.h>
-#include <CGAL/Triangulation_face_base_with_info_2.h>
-#include <CGAL/Constrained_Delaunay_triangulation_2.h>
-
-#include <iostream>
-#include <algorithm>
-#include <vector>
-
-/* If you want to use a viewer, you can use one of the following file
- * depending if you use vtk or qglviewer. */
-#ifdef CGAL_LCC_USE_QT
-#include "linear_cell_complex_3_viewer_qt.h"
-#else 
-#ifdef CGAL_LCC_USE_VTK
-#include "linear_cell_complex_3_viewer_vtk.h"
-#endif
-#endif
-
-typedef CGAL::Linear_cell_complex<3> LCC_3;
-typedef LCC_3::Dart_handle           Dart_handle;
-typedef LCC_3::Point                 Point;
-typedef LCC_3::FT                    FT;
-typedef LCC_3::Traits Traits;
-
-typedef CGAL::Triangulation_2_filtered_projection_traits_3<Traits> P_traits;
-typedef CGAL::Triangulation_vertex_base_with_info_2<Dart_handle,P_traits> Vb;
-
-struct Face_info {
-  bool exist_edge[3];
-  bool is_external;
-};
-
-typedef CGAL::Triangulation_face_base_with_info_2<Face_info,P_traits> Fb1;
-
-typedef CGAL::Constrained_triangulation_face_base_2<P_traits, Fb1>    Fb;
-typedef CGAL::Triangulation_data_structure_2<Vb,Fb>                   TDS;
-typedef CGAL::No_intersection_tag                                     Itag;
-typedef CGAL::Constrained_Delaunay_triangulation_2<P_traits, TDS,
-                                                   Itag>              CDT;
-
-bool is_external(CDT::Face_handle fh)
-{
-  return fh->info().is_external;
-}
-
-int number_of_existing_edge(CDT::Face_handle fh)
-{
-  unsigned res=0;
-  for (int i=0; i<3; ++i)
-    if (fh->info().exist_edge[i]) ++res;
-  return res;
-}
-
-int get_free_edge(CDT::Face_handle fh)
-{
-  CGAL_assertion( number_of_existing_edge(fh)==2 );
-  for (int i=0; i<3; ++i)
-    if (!fh->info().exist_edge[i]) return i;
-  
-  CGAL_assertion(false);
-  return -1;
-}
-
-void constrained_delaunay_triangulation(LCC_3 &lcc, Dart_handle d1)
-{
-  CGAL::set_ascii_mode(std::cout);
-  std::cout<<"Vertices: ";
-  for (LCC_3::Vertex_attribute_const_range::iterator
-         v=lcc.vertex_attributes().begin(),
-         vend=lcc.vertex_attributes().end(); v!=vend; ++v)
-    std::cout << lcc.point_of_vertex_attribute(v) << "; ";
-  std::cout<<std::endl;
- 
-  LCC_3::Vector normal = CGAL::compute_normal_of_cell_2(lcc,d1);
-  P_traits cdt_traits(normal);
-  CDT cdt(cdt_traits); 
-    
-  //inserting the constraints edge by edge
-  LCC_3::Dart_of_orbit_range<1>::iterator
-    it(lcc.darts_of_orbit<1>(d1).begin());
-
-  CDT::Vertex_handle previous=LCC_3::null_handle, first=LCC_3::null_handle,
-    vh=LCC_3::null_handle;
-
-   for (LCC_3::Dart_of_orbit_range<1>::iterator
-          itend(lcc.darts_of_orbit<1>(d1).end()); it!=itend; ++it)
-   {     
-     vh = cdt.insert(lcc.point(it));
-     vh->info()=it;
-     if( first==NULL ){
-       first=vh;
-     }
-     if( previous!=NULL){
-       CGAL_assertion( previous !=vh );
-       cdt.insert_constraint(previous,vh);
-     }
-
-     previous=vh;
-   }
-   cdt.insert_constraint(previous,first);
-   CGAL_assertion(cdt.is_valid());
-   
-   // sets mark is_external
-   for( CDT::All_faces_iterator fit = cdt.all_faces_begin(),
-          fitend = cdt.all_faces_end(); fit != fitend; ++fit)
-   {
-     fit->info().is_external = false;
-     fit->info().exist_edge[0]=false;
-     fit->info().exist_edge[1]=false;
-     fit->info().exist_edge[2]=false;
-   }
-	
-   std::queue<CDT::Face_handle> face_queue;
-      
-   face_queue.push(cdt.infinite_vertex()->face());
-   while(! face_queue.empty() )
-   {
-     CDT::Face_handle fh = face_queue.front();
-     face_queue.pop();
-     if(!fh->info().is_external)
-     {
-       fh->info().is_external = true;
-       for(int i = 0; i <3; ++i)
-       {
-         if(!cdt.is_constrained(std::make_pair(fh, i)))
-         {
-           face_queue.push(fh->neighbor(i));
-         }
-       }
-     }
-   }
-
-   for( CDT::Finite_edges_iterator eit = cdt.finite_edges_begin(),
-          eitend = cdt.finite_edges_end(); eit != eitend; ++eit)
-   {
-     CDT::Face_handle fh = eit->first;
-     int index = eit->second;
-     CDT::Face_handle opposite_fh = fh->neighbor(index);
-     if(cdt.is_constrained(std::make_pair(fh, index)))
-     {
-       fh->info().exist_edge[index]=true;
-       opposite_fh->info().exist_edge[cdt.mirror_index(fh,index)]=true;
-       
-       if ( !fh->info().is_external && number_of_existing_edge(fh)==2 )
-         face_queue.push(fh);
-       if ( !opposite_fh->info().is_external &&
-            number_of_existing_edge(opposite_fh)==2 )
-         face_queue.push(opposite_fh);
-     }
-   }
-   
-   while( !face_queue.empty() )
-   {
-     CDT::Face_handle fh = face_queue.front();
-     face_queue.pop();
-     CGAL_assertion( number_of_existing_edge(fh)>=2 ); // i.e. ==2 or ==3
-     CGAL_assertion( !fh->info().is_external );
-     
-     if (number_of_existing_edge(fh)==2)
-     {
-       int index = get_free_edge(fh);
-       CDT::Face_handle opposite_fh = fh->neighbor(index);
-
-       CGAL_assertion( !fh->info().exist_edge[index] );
-       CGAL_assertion( !opposite_fh->info().
-                       exist_edge[cdt.mirror_index(fh,index)] );
-       
-       const CDT::Vertex_handle va = fh->vertex(cdt. cw(index));
-       const CDT::Vertex_handle vb = fh->vertex(cdt.ccw(index));
-       
-       Dart_handle ndart=
-         CGAL::insert_cell_1_in_cell_2(lcc,va->info(),vb->info());         
-       va->info()=lcc.beta<2>(ndart);
-
-       fh->info().exist_edge[index]=true;
-       opposite_fh->info().exist_edge[cdt.mirror_index(fh,index)]=true;
-       
-       if ( !opposite_fh->info().is_external &&
-            number_of_existing_edge(opposite_fh)==2 )
-         face_queue.push(opposite_fh);
-     }
-   }   
-}
-
-Dart_handle make_facet(LCC_3& lcc,const std::vector<Point>& points)
-{
-  Dart_handle d =
-    CGAL::make_combinatorial_polygon<LCC_3>(lcc,(unsigned int)points.size());
-  for (unsigned int i=0; i<points.size(); ++i)
-  {
-    lcc.set_vertex_attribute_of_dart(d, lcc.create_vertex_attribute(points[i]));
-    d=lcc.beta<1>(d);
-  }
-  return d;
-}
-
-
-int main()
-{
-  LCC_3 lcc;
-
-  // Create one tetrahedra.
-  Dart_handle d1 = lcc.make_tetrahedron(Point(-1, 0, 0), Point(0, 2, 0),
-                                        Point(1, 0, 0), Point(1, 1, 2));
-
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-  constrained_delaunay_triangulation(lcc,d1);
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-  lcc.clear();
-  std::cout<<std::endl
-           <<"###################################################### \n"
-           <<std::endl;
-
-  // Create one hexahedron.
-  d1 = lcc.make_hexahedron(Point(0,0,0), Point(1,0,0), Point(1,1,0),
-                           Point(0,1,0), Point(0,1,1), Point(0,0,1),
-                           Point(1,0,1), Point(1,1,1));
-
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-  
-  constrained_delaunay_triangulation(lcc,d1);
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;  
-  
-  constrained_delaunay_triangulation(lcc,lcc.beta<2>(d1));
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-  lcc.clear();
-  std::cout<<std::endl
-           <<"###################################################### \n"
-           <<std::endl;
-  
-  std::vector<Point> points;
-  points.push_back(Point(0,0,0));
-  points.push_back(Point(5,15,0));
-  points.push_back(Point(8,18,0));
-  points.push_back(Point(12,5,0));
-  points.push_back(Point(8,3,0));
-  points.push_back(Point(8,-9,0));
-  points.push_back(Point(5,0,0));
-  points.push_back(Point(2,-3,2));
-  d1=make_facet(lcc,points);
-
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-#ifdef CGAL_LCC_USE_VIEWER
-  display_lcc(lcc);
-#endif // CGAL_LCC_USE_VIEWER
-  
-  constrained_delaunay_triangulation(lcc,d1);
-  lcc.display_characteristics(std::cout) << ", valid="
-                                         << lcc.is_valid()<<std::endl;
-#ifdef CGAL_LCC_USE_VIEWER
-  display_lcc(lcc);
-#endif // CGAL_LCC_USE_VIEWER
-
-  lcc.clear();
-  std::cout<<std::endl
-           <<"###################################################### \n"
-           <<std::endl;
-
-  return EXIT_SUCCESS;
-}
-
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h b/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
index 088d8c99be0..83716daa7e5 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
+++ b/Linear_cell_complex/examples/Linear_cell_complex/linear_cell_complex_3_viewer_qt.h
@@ -27,10 +27,15 @@
 #include <QGLViewer/qglviewer.h>
 #include <GL/gl.h>
 #include <CGAL/Linear_cell_complex.h>
-#include <CGAL/Cartesian.h>
 #include <CGAL/Cartesian_converter.h>
 
-typedef CGAL::Cartesian<double> Local_kernel;
+#include <CGAL/Triangulation_2_filtered_projection_traits_3.h>
+#include <CGAL/Triangulation_vertex_base_with_info_2.h>
+#include <CGAL/Triangulation_face_base_with_info_2.h>
+#include <CGAL/Constrained_Delaunay_triangulation_2.h>
+#include <CGAL/Constrained_triangulation_plus_2.h>
+
+typedef CGAL::Exact_predicates_inexact_constructions_kernel Local_kernel;
 typedef typename Local_kernel::Point_3  Local_point;
 typedef typename Local_kernel::Vector_3 Local_vector;
 
@@ -116,6 +121,24 @@ class SimpleLCCViewerQt : public QGLViewer
 {
   typedef typename LCC::Dart_handle Dart_handle;
 
+  struct Face_info
+  {
+    bool exist_edge[3];
+    bool is_external;
+    bool is_process;
+  };
+
+  typedef CGAL::Triangulation_2_filtered_projection_traits_3<CGAL::Exact_predicates_inexact_constructions_kernel> P_traits;
+  typedef CGAL::Triangulation_vertex_base_with_info_2<Local_vector,P_traits> Vb;
+  
+  typedef CGAL::Triangulation_face_base_with_info_2<Face_info,P_traits> Fb1;
+  
+  typedef CGAL::Constrained_triangulation_face_base_2<P_traits, Fb1>    Fb;
+  typedef CGAL::Triangulation_data_structure_2<Vb,Fb>                   TDS;
+  typedef CGAL::No_intersection_tag                                     Itag;
+  typedef CGAL::Constrained_Delaunay_triangulation_2<P_traits, TDS,
+                                                   Itag>              CDT;
+  
 public:
 
   // Constructor/Destructor
@@ -132,39 +155,170 @@ public:
   }
 
 protected :
+  void drawTriangleFace(Dart_handle dh, bool flat)
+  {
+    CGAL_assertion((lcc.template beta<1,1,1>(dh)==dh));
+    if(flat)
+    {
+      Local_vector normal = geomutils.get_facet_normal(lcc,dh);
+      ::glNormal3d(normal.x(), normal.y(), normal.z());
+    }
+    
+    for (typename LCC::template Dart_of_orbit_range<1>::const_iterator
+           orbitIter = lcc.template darts_of_orbit<1>(dh).begin();
+         orbitIter.cont(); ++orbitIter)
+    {
+      if(!flat)
+      {
+        // If Gouraud shading: 1 normal per vertex
+        Local_vector n = geomutils.get_vertex_normal(lcc,orbitIter);
+        ::glNormal3d(n.x(),n.y(),n.z());
+      }
+
+      Local_point p = geomutils.get_point(lcc, orbitIter);
+      ::glVertex3d(p.x(),p.y(),p.z());
+    }
+    
+  }
+  
+  void drawNonTriangleFace(Dart_handle dh, bool flat)
+  {
+    CGAL_assertion((lcc.template beta<1,1,1>(dh)!=dh));
+    Local_vector normal = geomutils.get_facet_normal(lcc,dh);
+
+    P_traits cdt_traits(normal);
+    CDT cdt(cdt_traits);
+    
+    // Iterates on the vector of facet handles
+    typename CDT::Vertex_handle previous = NULL, first = NULL;
+    for (typename LCC::template Dart_of_orbit_range<1>::const_iterator
+           he_circ = lcc.template darts_of_orbit<1>(dh).begin(),
+           he_circ_end = lcc.template darts_of_orbit<1>(dh).end();
+         he_circ!=he_circ_end; ++he_circ)
+    {
+      typename CDT::Vertex_handle vh = cdt.insert(geomutils.get_point(lcc, he_circ));
+      if(first == NULL)
+      { first = vh; }
+      vh->info() = geomutils.get_vertex_normal(lcc, he_circ);
+      if(previous!=NULL && previous != vh)
+      { cdt.insert_constraint(previous, vh); }
+      previous = vh;
+    }
+    if (previous!=NULL)
+      cdt.insert_constraint(previous, first);
+    
+    // sets mark is_external
+    for(typename CDT::All_faces_iterator fit = cdt.all_faces_begin(),
+          fitend = cdt.all_faces_end(); fit!=fitend; ++fit)
+    {
+      fit->info().is_external = true;
+      fit->info().is_process = false;
+    }
+    //check if the facet is external or internal
+    std::queue<typename CDT::Face_handle> face_queue;
+    typename CDT::Face_handle face_internal = NULL;
+    face_queue.push(cdt.infinite_vertex()->face());
+    while(! face_queue.empty() )
+    {
+      typename CDT::Face_handle fh = face_queue.front();
+      face_queue.pop();
+      if(!fh->info().is_process)
+      {
+        fh->info().is_process = true;
+        for(int i = 0; i <3; ++i)
+        {
+          if(!cdt.is_constrained(std::make_pair(fh, i)))
+          {
+            face_queue.push(fh->neighbor(i));
+          }
+          else if (face_internal==NULL)
+          {
+            face_internal = fh->neighbor(i);
+          }
+        }
+      }
+    }
+
+    if ( face_internal!=NULL )
+      face_queue.push(face_internal);
+    
+    while(! face_queue.empty() )
+    {
+      typename CDT::Face_handle fh = face_queue.front();
+      face_queue.pop();
+      if(!fh->info().is_process)
+      {
+        fh->info().is_process = true;
+        fh->info().is_external = false;
+        for(int i = 0; i <3; ++i)
+        {
+          if(!cdt.is_constrained(std::make_pair(fh, i)))
+          {
+            face_queue.push(fh->neighbor(i));
+          }
+        }
+      }
+    }
+
+    //iterates on the internal faces to draw the corresponding triangles
+    for(typename CDT::Finite_faces_iterator ffit = cdt.finite_faces_begin(),
+          ffitend = cdt.finite_faces_end(); ffit != ffitend; ++ffit)
+    {
+      if(!ffit->info().is_external)
+      {
+        if(flat)
+        {
+          ::glNormal3d(normal.x(), normal.y(), normal.z());
+        }
+        else
+        {
+          ::glNormal3d(ffit->vertex(0)->info().x(),
+                       ffit->vertex(0)->info().y(),
+                       ffit->vertex(0)->info().z());
+        }
+        
+        ::glVertex3d(ffit->vertex(0)->point().x(),
+                     ffit->vertex(0)->point().y(),
+                     ffit->vertex(0)->point().z());
+
+        if(!flat)
+        {
+          ::glNormal3d(ffit->vertex(1)->info().x(),
+                       ffit->vertex(1)->info().y(),
+                       ffit->vertex(1)->info().z());
+        }
+        ::glVertex3d(ffit->vertex(1)->point().x(),
+                     ffit->vertex(1)->point().y(),
+                     ffit->vertex(1)->point().z());
+
+        if(!flat)
+        {
+          ::glNormal3d(ffit->vertex(2)->info().x(),
+                       ffit->vertex(2)->info().y(),
+                       ffit->vertex(2)->info().z());
+        }
+        ::glVertex3d(ffit->vertex(2)->point().x(),
+                     ffit->vertex(2)->point().y(),
+                     ffit->vertex(2)->point().z());
+      }
+    }
+  }
+  
   void drawAllFaces(bool flat)
   {
+    ::glColor3f(1.0f, .7f, .7f);
+    ::glBegin(GL_TRIANGLES);
     for(typename LCC::template One_dart_per_cell_range<2>::iterator
           dartIter=lcc.template one_dart_per_cell<2>().begin();
         dartIter.cont(); ++dartIter)
     {
-      Dart_handle& dart = dartIter;
-      ::glBegin(GL_POLYGON);
-      ::glColor3f(1.0f, .7f, .7f);
-
-      if(flat)
-      {
-        Local_vector normal = geomutils.get_facet_normal(lcc,dart);
-        ::glNormal3d(normal.x(), normal.y(), normal.z());
-      }
-
-      for (typename LCC::template Dart_of_orbit_range<1>::const_iterator
-             orbitIter = lcc.template darts_of_orbit<1>(dart).begin();
-           orbitIter.cont(); ++orbitIter)
-      {
-        if(!flat)
-        {
-          // If Gouraud shading: 1 normal per vertex
-          Local_vector n = geomutils.get_vertex_normal(lcc,orbitIter);
-          ::glNormal3d(n.x(),n.y(),n.z());
-        }
-
-        Local_point p = geomutils.get_point(lcc, orbitIter);
-        ::glVertex3d(p.x(),p.y(),p.z());
-      }
-
-      ::glEnd();
+      if (lcc.template beta<1,1,1>(dartIter)!=dartIter)
+        drawNonTriangleFace(dartIter, flat);
+      else
+        drawTriangleFace(dartIter, flat);
+      
     }
+    ::glEnd();    
   }
 
   void drawAllEdges()
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/voronoi_2.cpp b/Linear_cell_complex/examples/Linear_cell_complex/voronoi_2.cpp
index 24c117476af..da707cf9eb8 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/voronoi_2.cpp
+++ b/Linear_cell_complex/examples/Linear_cell_complex/voronoi_2.cpp
@@ -5,14 +5,9 @@
 #include <iostream>
 #include <fstream>
 
-/* If you want to use a viewer, you can use one of the following file
- * depending if you use vtk or qglviewer. */
+/* If you want to use a viewer, you can use qglviewer. */
 #ifdef CGAL_LCC_USE_QT
 #include "linear_cell_complex_3_viewer_qt.h"
-#else 
-#ifdef CGAL_LCC_USE_VTK
-#include "linear_cell_complex_3_viewer_vtk.h"
-#endif
 #endif
 
 /* // If you want to use exact constructions.
diff --git a/Linear_cell_complex/examples/Linear_cell_complex/voronoi_3.cpp b/Linear_cell_complex/examples/Linear_cell_complex/voronoi_3.cpp
index 1a21c4236bd..7e9d072ba0d 100644
--- a/Linear_cell_complex/examples/Linear_cell_complex/voronoi_3.cpp
+++ b/Linear_cell_complex/examples/Linear_cell_complex/voronoi_3.cpp
@@ -5,14 +5,9 @@
 #include <iostream>
 #include <fstream>
 
-/* If you want to use a viewer, you can use one of the following file
- * depending if you use vtk or qglviewer. */
+/* If you want to use a viewer, you can use one qglviewer. */
 #ifdef CGAL_LCC_USE_QT
 #include "linear_cell_complex_3_viewer_qt.h"
-#else 
-#ifdef CGAL_LCC_USE_VTK
-#include "linear_cell_complex_3_viewer_vtk.h"
-#endif
 #endif
 
 /* // If you want to use exact constructions.