diff --git a/.gitattributes b/.gitattributes
index 95b797329bb..ec88acaa08f 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1687,6 +1687,10 @@ Kernel_23/doc_tex/Kernel_23_ref/fig/compare_x_at_y.pdf -text svneol=unset#applic
 Kernel_23/doc_tex/Kernel_23_ref/fig/transvecthree.gif -text svneol=unset#image/gif
 Kernel_23/doc_tex/Kernel_23_ref/fig/transvectwo.gif -text svneol=unset#image/gif
 Kernel_23/doc_tex/Kernel_23_ref/radical_line.tex -text
+Kernel_23/examples/Kernel_23/MyConstruct_bbox_2.h -text
+Kernel_23/examples/Kernel_23/MyConstruct_coord_iterator.h -text
+Kernel_23/examples/Kernel_23/MyConstruct_point_2.h -text
+Kernel_23/examples/Kernel_23/MyPointC2_iostream.h -text
 Kernel_23/examples/Kernel_23/cartesian_converter.cpp -text
 Kernel_23/include/CGAL/functions_on_enums.h -text
 Kernel_23/include/CGAL/internal/Projection_traits_3.h -text
diff --git a/Kernel_23/doc_tex/Kernel_23/extensible_kernel.tex b/Kernel_23/doc_tex/Kernel_23/extensible_kernel.tex
index c6976b00090..5c457079244 100644
--- a/Kernel_23/doc_tex/Kernel_23/extensible_kernel.tex
+++ b/Kernel_23/doc_tex/Kernel_23/extensible_kernel.tex
@@ -25,58 +25,7 @@ Assume you have the following point class, where the coordinates are
 stored in an array of \ccc{doubles}, where we have another data member
 \ccc{color}, which shows up in the constructor.
 
-\ccHtmlLinksOff
-\begin{ccExampleCode}
-class MyPointC2 {
-
-private:
-  double vec[2];
-  int col;
-
-public:
-
-  MyPointC2()
-    : col(0)
-  {
-    *vec = 0;
-    *(vec+1) = 0;
-  }
-
-  
-  MyPointC2(const double x, const double y, int c)
-    : col(c)
-  {
-    *vec = x;
-    *(vec+1) = y;
-  }
-
-  const double& x() const  { return *vec; }
-
-  const double& y() const { return *(vec+1); }
-
-  double & x() { return *vec; }
-
-  double& y() { return *(vec+1); }
-
-  int color() const { return col; }
-
-  int& color() { return col; }
-  
-  
-  bool operator==(const MyPointC2 &p) const
-  {
-    return ( *vec == *(p.vec) )  && ( *(vec+1) == *(p.vec + 1) && ( col == p.col) );
-  }
-
-  bool operator!=(const MyPointC2 &p) const
-  {
-      return !(*this == p);
-  }
-
-};
-\end{ccExampleCode}
-\ccHtmlLinksOn
-
+\ccIncludeExampleCode{Kernel_23/MyPointC2.h}
 
 As said earlier the class is pretty minimalistic, for
 example it has no \ccc{bbox()} method.  One
@@ -89,44 +38,14 @@ use of the functor \ccc{Kernel::Construct_bbox_2}.
 To make the right thing happen with \ccc{MyPointC2} we
 have to provide the following functor.
 
-\ccHtmlLinksOff
-\begin{ccExampleCode}
-template <class ConstructBbox_2>
-class MyConstruct_bbox_2 : public ConstructBbox_2 {
-public:
-  using ConstructBbox_2::operator();
-
-  CGAL::Bbox_2 operator()(const typename MyPointC2& p) const {
-    return CGAL::Bbox_2(p.x(), p.y(), p.x(), p.y());
-  }
-};
-\end{ccExampleCode}
-\ccHtmlLinksOn
-
+\ccIncludeExampleCode{Kernel_23/MyConstruct_bbox_2.h}
 
 Things are similar for random access to the \ccHtmlNoLinksFrom{Cartesian}
 coordinates of a point. As the coordinates are stored
 in an array of \ccc{doubles} we can use \ccc{double*} as
 random access iterator.
 
-\ccHtmlLinksOff
-\begin{ccExampleCode}
-class MyConstruct_coord_iterator {
-public:
-  const double* operator()(const MyPointC2& p)
-  {
-    return &p.x();
-  }
-
-  const double* operator()(const MyPointC2& p, int)
-  {
-    const double* pyptr = &p.y();
-    pyptr++;
-    return pyptr;
-  }
-};
-\end{ccExampleCode}
-\ccHtmlLinksOn
+\ccIncludeExampleCode{Kernel_23/MyConstruct_coord_iterator.h}
 
 The last functor we have to provide is the one which constructs
 points. That is you are not forced to add the constructor 
@@ -135,55 +54,14 @@ homogeneous coordinates.
 The functor is a kind of glue layer between the \cgal\ algorithms
 and your class.
 
-\ccHtmlLinksOff
-\begin{ccExampleCode}
- template <typename K>
-  class MyConstruct_point_2
-  {
-    typedef typename K::RT         RT;
-    typedef typename K::Point_2    Point_2;
-  public:
-    typedef Point_2          result_type;
-
-    Point_2
-    operator()(CGAL::Origin o) const
-    { return Point_2(0,0, 0); }
-
-    Point_2
-    operator()(const RT& x, const RT& y) const
-    { return Point_2(x, y, 0); }
-
-    
-    // We need this one, as such a functor is in the Filtered_kernel
-    Point_2
-    operator()(const RT& x, const RT& y, const RT& w) const
-    { 
-      if(w != 1){
-	return Point_2(x/w, y/w, 0); 
-      } else {
-	return Point_2(x,y, 0);
-      }
-    }
-  };
-
-\end{ccExampleCode}
-\ccHtmlLinksOn
-
+\ccIncludeExampleCode{Kernel_23/MyConstruct_point_2.h}
 
 Now we are ready to put the puzzle together. We won't explain it in
 detail, but you see that there are \ccc{typedefs} to the new point
 class and the functors. All the other types are inherited.
 
-
-
-
-
 \ccIncludeExampleCode{Kernel_23/MyKernel.h}
 
-
-
-
-
 Finally, we give an example how this new kernel can be used.
 Predicates and constructions work with the new point, they
 can be a used to construct segments and triangles with, and
diff --git a/Kernel_23/examples/Kernel_23/MyConstruct_bbox_2.h b/Kernel_23/examples/Kernel_23/MyConstruct_bbox_2.h
new file mode 100644
index 00000000000..e557f398b80
--- /dev/null
+++ b/Kernel_23/examples/Kernel_23/MyConstruct_bbox_2.h
@@ -0,0 +1,15 @@
+#ifndef MYCONSTRUCT_BBOX_2_H
+#define MYCONSTRUCT_BBOX_2_H
+
+
+template <class ConstructBbox_2>
+class MyConstruct_bbox_2 : public ConstructBbox_2 {
+public:
+  using ConstructBbox_2::operator();
+
+  CGAL::Bbox_2 operator()(const MyPointC2& p) const {
+    return CGAL::Bbox_2(p.x(), p.y(), p.x(), p.y());
+  }
+};
+
+#endif //MYCONSTRUCT_BBOX_2_H
diff --git a/Kernel_23/examples/Kernel_23/MyConstruct_coord_iterator.h b/Kernel_23/examples/Kernel_23/MyConstruct_coord_iterator.h
new file mode 100644
index 00000000000..d3440644f32
--- /dev/null
+++ b/Kernel_23/examples/Kernel_23/MyConstruct_coord_iterator.h
@@ -0,0 +1,19 @@
+#ifndef MYCONSTRUCT_COORD_ITERATOR_H
+#define MYCONSTRUCT_COORD_ITERATOR_H
+
+class MyConstruct_coord_iterator {
+public:
+  const double* operator()(const MyPointC2& p)
+  {
+    return &p.x();
+  }
+
+  const double* operator()(const MyPointC2& p, int)
+  {
+    const double* pyptr = &p.y();
+    pyptr++;
+    return pyptr;
+  }
+};
+
+#endif //MYCONSTRUCT_COORD_ITERATOR_H
diff --git a/Kernel_23/examples/Kernel_23/MyConstruct_point_2.h b/Kernel_23/examples/Kernel_23/MyConstruct_point_2.h
new file mode 100644
index 00000000000..f57eccee7dd
--- /dev/null
+++ b/Kernel_23/examples/Kernel_23/MyConstruct_point_2.h
@@ -0,0 +1,66 @@
+#ifndef MYCONSTRUCT_POINT_2_H
+#define MYCONSTRUCT_POINT_2_H
+
+template <typename K, typename OldK>
+class MyConstruct_point_2
+{
+  typedef typename K::RT         RT;
+  typedef typename K::Point_2    Point_2;
+  typedef typename K::Line_2     Line_2;
+  typedef typename Point_2::Rep  Rep;
+public:
+  typedef Point_2                result_type;
+
+  // Note : the CGAL::Return_base_tag is really internal CGAL stuff.
+  // Unfortunately it is needed for optimizing away copy-constructions,
+  // due to current lack of delegating constructors in the C++ standard.
+  Rep // Point_2
+  operator()(CGAL::Return_base_tag, CGAL::Origin o) const
+  { return Rep(o); }
+
+  Rep // Point_2
+  operator()(CGAL::Return_base_tag, const RT& x, const RT& y) const
+  { return Rep(x, y); }
+
+  Rep // Point_2
+  operator()(CGAL::Return_base_tag, const RT& x, const RT& y, const RT& w) const
+  { return Rep(x, y, w); }
+
+  Point_2
+  operator()(CGAL::Origin o) const
+  { return MyPointC2(0, 0, 0); }
+
+  Point_2
+  operator()(const RT& x, const RT& y) const
+  {
+    return MyPointC2(x, y, 0);
+  }
+
+  Point_2
+  operator()(const Line_2& l) const
+  {
+    typename OldK::Construct_point_2 base_operator;
+    Point_2 p = base_operator(l);
+    return p;
+  }
+
+  Point_2
+  operator()(const Line_2& l, int i) const
+  {
+    typename OldK::Construct_point_2 base_operator;
+    return base_operator(l, i);
+  }
+
+  // We need this one, as such a functor is in the Filtered_kernel
+  Point_2
+  operator()(const RT& x, const RT& y, const RT& w) const
+  {
+    if(w != 1){
+      return MyPointC2(x/w, y/w, 0);
+    } else {
+      return MyPointC2(x,y, 0);
+    }
+  }
+};
+
+#endif //MYCONSTRUCT_POINT_2_H
diff --git a/Kernel_23/examples/Kernel_23/MyKernel.cpp b/Kernel_23/examples/Kernel_23/MyKernel.cpp
index ccb0ee00652..85ad7eab68d 100644
--- a/Kernel_23/examples/Kernel_23/MyKernel.cpp
+++ b/Kernel_23/examples/Kernel_23/MyKernel.cpp
@@ -4,7 +4,7 @@
 #include <CGAL/squared_distance_2.h>
 #include <cassert>
 #include "MyKernel.h"
-
+#include "MyPointC2_iostream.h"
 
 typedef MyKernel<double>                   MK;
 typedef CGAL::Filtered_kernel_adaptor<MK>  K;
diff --git a/Kernel_23/examples/Kernel_23/MyKernel.h b/Kernel_23/examples/Kernel_23/MyKernel.h
index b5370e1edaf..bb41efb2639 100644
--- a/Kernel_23/examples/Kernel_23/MyKernel.h
+++ b/Kernel_23/examples/Kernel_23/MyKernel.h
@@ -4,6 +4,9 @@
 #include <CGAL/Cartesian.h>
 #include "MyPointC2.h"
 #include "MySegmentC2.h"
+#include "MyConstruct_bbox_2.h"
+#include "MyConstruct_coord_iterator.h"
+#include "MyConstruct_point_2.h"
 
 // K_ is the new kernel, and K_Base is the old kernel
 template < typename K_, typename K_Base >
diff --git a/Kernel_23/examples/Kernel_23/MyPointC2.h b/Kernel_23/examples/Kernel_23/MyPointC2.h
index 6c93c0cc00d..de1c7ee6cd6 100644
--- a/Kernel_23/examples/Kernel_23/MyPointC2.h
+++ b/Kernel_23/examples/Kernel_23/MyPointC2.h
@@ -54,136 +54,4 @@ public:
 
 };
 
-template <class ConstructBbox_2>
-class MyConstruct_bbox_2 : public ConstructBbox_2 {
-public:
-  using ConstructBbox_2::operator();
-
-  CGAL::Bbox_2 operator()(const MyPointC2& p) const {
-    return CGAL::Bbox_2(p.x(), p.y(), p.x(), p.y());
-  }
-};
-
-
-class MyConstruct_coord_iterator {
-public:
-  const double* operator()(const MyPointC2& p)
-  {
-    return &p.x();
-  }
-
-  const double* operator()(const MyPointC2& p, int)
-  {
-    const double* pyptr = &p.y();
-    pyptr++;
-    return pyptr;
-  }
-};
-
-  template <typename K, typename OldK>
-  class MyConstruct_point_2
-  {
-    typedef typename K::RT         RT;
-    typedef typename K::Point_2    Point_2;
-    typedef typename K::Line_2     Line_2;
-    typedef typename Point_2::Rep  Rep;
-  public:
-    typedef Point_2                result_type;
-
-    // Note : the CGAL::Return_base_tag is really internal CGAL stuff.
-    // Unfortunately it is needed for optimizing away copy-constructions,
-    // due to current lack of delegating constructors in the C++ standard.
-    Rep // Point_2
-    operator()(CGAL::Return_base_tag, CGAL::Origin o) const
-    { return Rep(o); }
-
-    Rep // Point_2
-    operator()(CGAL::Return_base_tag, const RT& x, const RT& y) const
-    { return Rep(x, y); }
-
-    Rep // Point_2
-    operator()(CGAL::Return_base_tag, const RT& x, const RT& y, const RT& w) const
-    { return Rep(x, y, w); }
-
-    Point_2
-    operator()(CGAL::Origin o) const
-    { return MyPointC2(0, 0, 0); }
-
-    Point_2
-    operator()(const RT& x, const RT& y) const
-    {
-      return MyPointC2(x, y, 0);
-    }
-
-    Point_2
-    operator()(const Line_2& l) const
-    {
-      typename OldK::Construct_point_2 base_operator;
-      Point_2 p = base_operator(l);
-      return p;
-    }
-
-    Point_2
-    operator()(const Line_2& l, int i) const
-    {
-      typename OldK::Construct_point_2 base_operator;
-      return base_operator(l, i);
-    }
-
-    // We need this one, as such a functor is in the Filtered_kernel
-    Point_2
-    operator()(const RT& x, const RT& y, const RT& w) const
-    {
-      if(w != 1){
-	return MyPointC2(x/w, y/w, 0);
-      } else {
-	return MyPointC2(x,y, 0);
-      }
-    }
-  };
-
-std::ostream &
-operator<<(std::ostream &os, const MyPointC2 &p)
-{
-    switch(os.iword(CGAL::IO::mode)) {
-    case CGAL::IO::ASCII :
-        return os << p.x() << ' ' << p.y() << ' ' << p.color();
-    case CGAL::IO::BINARY :
-        CGAL::write(os, p.x());
-        CGAL::write(os, p.y());
-        CGAL::write(os, p.color());
-        return os;
-    default:
-        return os << "MyPointC2(" << p.x() << ", " << p.y() << ", " << p.color() << ')';
-    }
-}
-
-
-
-std::istream &
-operator>>(std::istream &is, MyPointC2 &p)
-{
-    double x, y;
-    int c;
-    switch(is.iword(CGAL::IO::mode)) {
-    case CGAL::IO::ASCII :
-      is >> x >> y >> c;
-        break;
-    case CGAL::IO::BINARY :
-        CGAL::read(is, x);
-        CGAL::read(is, y);
-	CGAL::read(is, c);
-        break;
-    default:
-        std::cerr << "" << std::endl;
-        std::cerr << "Stream must be in ascii or binary mode" << std::endl;
-        break;
-    }
-    if (is) {
-      p = MyPointC2(x, y, c);
-    }
-    return is;
-}
-
-
 #endif // MY_POINTC2_H
diff --git a/Kernel_23/examples/Kernel_23/MyPointC2_iostream.h b/Kernel_23/examples/Kernel_23/MyPointC2_iostream.h
new file mode 100644
index 00000000000..462ea205ef5
--- /dev/null
+++ b/Kernel_23/examples/Kernel_23/MyPointC2_iostream.h
@@ -0,0 +1,46 @@
+#ifndef MYPOINTC2_IOSTREAM_H
+#define MYPOINTC2_IOSTREAM_H
+
+std::ostream &
+operator<<(std::ostream &os, const MyPointC2 &p)
+{
+    switch(os.iword(CGAL::IO::mode)) {
+    case CGAL::IO::ASCII :
+        return os << p.x() << ' ' << p.y() << ' ' << p.color();
+    case CGAL::IO::BINARY :
+        CGAL::write(os, p.x());
+        CGAL::write(os, p.y());
+        CGAL::write(os, p.color());
+        return os;
+    default:
+        return os << "MyPointC2(" << p.x() << ", " << p.y() << ", " << p.color() << ')';
+    }
+}
+
+
+
+std::istream &
+operator>>(std::istream &is, MyPointC2 &p)
+{
+    double x, y;
+    int c;
+    switch(is.iword(CGAL::IO::mode)) {
+    case CGAL::IO::ASCII :
+      is >> x >> y >> c;
+        break;
+    case CGAL::IO::BINARY :
+        CGAL::read(is, x);
+        CGAL::read(is, y);
+	CGAL::read(is, c);
+        break;
+    default:
+        std::cerr << "" << std::endl;
+        std::cerr << "Stream must be in ascii or binary mode" << std::endl;
+        break;
+    }
+    if (is) {
+      p = MyPointC2(x, y, c);
+    }
+    return is;
+}
+#endif //MYPOINTC2_IOSTREAM_H