diff --git a/Combinatorial_map/include/CGAL/Cell_attribute.h b/Combinatorial_map/include/CGAL/Cell_attribute.h
index 245e9a07d09..a7c5861a90a 100644
--- a/Combinatorial_map/include/CGAL/Cell_attribute.h
+++ b/Combinatorial_map/include/CGAL/Cell_attribute.h
@@ -24,6 +24,11 @@
 
 namespace CGAL {
 
+  namespace internal {
+    template<typename CMap, unsigned int i, typename T>
+    struct Decrease_attribute_functor_run;
+  }
+
   template < unsigned int, class, class, class, class >
   class Combinatorial_map_base;
 
diff --git a/Combinatorial_map/include/CGAL/Combinatorial_map_basic_operations.h b/Combinatorial_map/include/CGAL/Combinatorial_map_basic_operations.h
index ae57c78837b..3e3ca256093 100644
--- a/Combinatorial_map/include/CGAL/Combinatorial_map_basic_operations.h
+++ b/Combinatorial_map/include/CGAL/Combinatorial_map_basic_operations.h
@@ -20,6 +20,7 @@
 #ifndef CGAL_COMBINATORIAL_MAP_BASIC_OPERATIONS_H
 #define CGAL_COMBINATORIAL_MAP_BASIC_OPERATIONS_H 1
 
+#include <CGAL/Combinatorial_map_iterators_base.h>
 #include <boost/type_traits/is_same.hpp>
 #include <CGAL/tags.h>
 
diff --git a/Combinatorial_map/include/CGAL/Combinatorial_map_insertions.h b/Combinatorial_map/include/CGAL/Combinatorial_map_insertions.h
index 0885b027f05..958671ca6a3 100644
--- a/Combinatorial_map/include/CGAL/Combinatorial_map_insertions.h
+++ b/Combinatorial_map/include/CGAL/Combinatorial_map_insertions.h
@@ -21,6 +21,7 @@
 #define CGAL_COMBINATORIAL_MAP_INSERTIONS_H
 
 #include <deque>
+#include <CGAL/config.h>
 
 namespace CGAL
 {
diff --git a/Combinatorial_map/include/CGAL/Combinatorial_map_operations.h b/Combinatorial_map/include/CGAL/Combinatorial_map_operations.h
index 69188e83f25..f5cbabecce3 100644
--- a/Combinatorial_map/include/CGAL/Combinatorial_map_operations.h
+++ b/Combinatorial_map/include/CGAL/Combinatorial_map_operations.h
@@ -22,6 +22,9 @@
 
 #include <CGAL/Combinatorial_map_basic_operations.h>
 #include <CGAL/Combinatorial_map_insertions.h>
+#include <CGAL/internal/Combinatorial_map_sewable.h>
+#include <CGAL/internal/Combinatorial_map_group_functors.h>
+
 #include <deque>
 #include <stack>
 
diff --git a/Combinatorial_map/include/CGAL/Combinatorial_map_storages.h b/Combinatorial_map/include/CGAL/Combinatorial_map_storages.h
index d513b818ad1..31643829446 100644
--- a/Combinatorial_map/include/CGAL/Combinatorial_map_storages.h
+++ b/Combinatorial_map/include/CGAL/Combinatorial_map_storages.h
@@ -23,6 +23,7 @@
 #include <CGAL/Handle_hash_function.h>
 
 #include <CGAL/Compact_container.h>
+#include <bitset>
 
 #include <boost/config.hpp>
 #if  (BOOST_GCC >= 40900)
@@ -32,6 +33,11 @@ _Pragma("GCC diagnostic ignored \"-Warray-bounds\"")
 
 namespace CGAL {
 
+  namespace internal {
+    template <typename M>
+    class Combinatorial_map_helper;
+  }
+
   /** @file Combinatorial_map_storages.h
    * Definition of storages for dD Combinatorial map.
    */
diff --git a/Combinatorial_map/include/CGAL/Dart.h b/Combinatorial_map/include/CGAL/Dart.h
index 03fae724afe..6287ebdf32f 100644
--- a/Combinatorial_map/include/CGAL/Dart.h
+++ b/Combinatorial_map/include/CGAL/Dart.h
@@ -26,6 +26,13 @@
 
 namespace CGAL {
 
+  namespace internal {
+    template <typename M>
+    class Reverse_orientation_of_map_functor;
+    template <typename M>
+    class Reverse_orientation_of_connected_component_functor;
+  }
+
   /** @file Dart.h
    * Definition of nD dart.
    */