diff --git a/Interpolation/doc_tex/Interpolation_ref/farin_c1_interpolation.tex b/Interpolation/doc_tex/Interpolation_ref/farin_c1_interpolation.tex
index 9abc5a573e1..fa12a018bb9 100644
--- a/Interpolation/doc_tex/Interpolation_ref/farin_c1_interpolation.tex
+++ b/Interpolation/doc_tex/Interpolation_ref/farin_c1_interpolation.tex
@@ -26,7 +26,9 @@ associating a point to a (non-normalized) barycentric coordinate.  See
   farin_c1_interpolation(RandomAccessIterator first,
   RandomAccessIterator beyond, const typename
   std::iterator_traits<RandomAccessIterator>::value_type::second_type&
-  norm, Functor function_value, GradFunctor function_gradient, const
+  norm, const typename
+  std::iterator_traits<ForwardIterator>::value_type::first_type& p,
+  Functor function_value, GradFunctor function_gradient, const
   Traits& traits);} {generates the interpolated function value
   computed by Farin's interpolant \cite{f-sodt-90}.  See also
   \ccc{sibson_c1_interpolation}.  \ccPrecond{\ccc{norm} $\neq 0$.
diff --git a/Interpolation/doc_tex/Interpolation_ref/linear_interpolation.tex b/Interpolation/doc_tex/Interpolation_ref/linear_interpolation.tex
index 34ef09541b4..57a98760b9e 100644
--- a/Interpolation/doc_tex/Interpolation_ref/linear_interpolation.tex
+++ b/Interpolation/doc_tex/Interpolation_ref/linear_interpolation.tex
@@ -19,7 +19,7 @@ values which must be provided via a functor.
 \ccInclude{CGAL/interpolation_functions.h}
 
 \ccFunction{template < class ForwardIterator, class Functor> typename
-  Functor::result_type linear_interpolation(ForwardIterator first,
+  Functor::result_type::first_type linear_interpolation(ForwardIterator first,
   ForwardIterator beyond, const typename
   std::iterator_traits<ForwardIterator>::value_type::second_type&
   norm, Functor function_values);}{\ccc{ForwardIterator::value_type}
diff --git a/Interpolation/doc_tex/Interpolation_ref/quadratic_interpolation.tex b/Interpolation/doc_tex/Interpolation_ref/quadratic_interpolation.tex
index 62618781465..ad169907a9a 100644
--- a/Interpolation/doc_tex/Interpolation_ref/quadratic_interpolation.tex
+++ b/Interpolation/doc_tex/Interpolation_ref/quadratic_interpolation.tex
@@ -25,7 +25,9 @@ See \ccc{sibson_c1_interpolation}.
   GradFunctor, class Traits> typename Functor::result_type
   quadratic_interpolation(ForwardIterator first, ForwardIterator
   beyond, const typename std::iterator_traits<ForwardIterator>::
-  value_type::second_type& norm, Functor function_value, GradFunctor
+  value_type::second_type& norm, 
+  const typename std::iterator_traits<ForwardIterator>::value_type::
+  first_type& p, Functor function_value, GradFunctor
   function_gradient,const Traits& traits);} {
  % \ccc{ForwardIterator::value_type} is a pair associating a point to a
  % (non-normalized) barycentric coordinate.  \ccc{norm} is the
diff --git a/Interpolation/doc_tex/Interpolation_ref/sibson_c1_interpolation.tex b/Interpolation/doc_tex/Interpolation_ref/sibson_c1_interpolation.tex
index 48860ebf857..eff352942df 100644
--- a/Interpolation/doc_tex/Interpolation_ref/sibson_c1_interpolation.tex
+++ b/Interpolation/doc_tex/Interpolation_ref/sibson_c1_interpolation.tex
@@ -83,7 +83,9 @@ function gradient given a point.
   sibson_c1_interpolation_square(ForwardIterator first,
   ForwardIterator beyond, const typename
   std::iterator_traits<ForwardIterator>::value_type::second_type&
-  norm, Functor function_value, GradFunctor function_gradient,const
+  norm,  const typename
+  std::iterator_traits<ForwardIterator>::value_type::first_type& p,
+  Functor function_value, GradFunctor function_gradient,const
   Traits& traits);} {The same as above except that no square root
   operation is needed for \ccc{FT}.}