diff --git a/include/core/problem/problem.h b/include/core/problem/problem.h
index d2de44d0b38a58d5313a8f07574755e4866260d6..46500c6e225e5f2f07928c2656d950a1462749ad 100644
--- a/include/core/problem/problem.h
+++ b/include/core/problem/problem.h
@@ -62,12 +62,6 @@ struct PriorOptions
 };
 WOLF_STRUCT_PTR_TYPEDEFS(PriorOptions);
 
-struct Reference
-{
-    StateBlockPtr p_ptr;
-    StateBlockPtr o_ptr;
-};
-
 /** \brief Wolf problem node element in the Wolf Tree
  */
 class Problem : public std::enable_shared_from_this<Problem>
@@ -96,8 +90,6 @@ class Problem : public std::enable_shared_from_this<Problem>
         VectorComposite  transformation_;
         mutable std::mutex mut_transform_;
 
-        Reference local_reference_;
-
       private:  // CAUTION: THESE METHODS ARE PRIVATE, DO NOT MAKE THEM PUBLIC !!
         Problem(const std::string& _frame_structure, SizeEigen _dim, MapBasePtr _map); // USE create() below !!
         void setup();
@@ -113,10 +105,6 @@ class Problem : public std::enable_shared_from_this<Problem>
     public:
         SizeEigen getDim() const;
         const StateStructure& getFrameStructure() const;
-        StateBlockPtr getLocalReferenceP();
-        StateBlockConstPtr getLocalReferenceP() const;
-        StateBlockPtr getLocalReferenceO();
-        StateBlockConstPtr getLocalReferenceO() const;
 
     protected:
         void appendToStructure(const StateStructure& _structure);
@@ -465,26 +453,6 @@ class Problem : public std::enable_shared_from_this<Problem>
 namespace wolf
 {
 
-inline StateBlockPtr Problem::getLocalReferenceP()
-{
-    return local_reference_.p_ptr;
-}
-
-inline StateBlockConstPtr Problem::getLocalReferenceP() const
-{
-    return local_reference_.p_ptr;
-}
-
-inline StateBlockPtr Problem::getLocalReferenceO()
-{
-    return local_reference_.o_ptr;
-}
-
-inline StateBlockConstPtr Problem::getLocalReferenceO() const
-{
-    return local_reference_.o_ptr;
-}
-
 inline TreeManagerBaseConstPtr Problem::getTreeManager() const
 {
     return tree_manager_;