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diff --git a/src/boundary/extendedFiniteDifferenceBoundary2D.h b/src/boundary/extendedFiniteDifferenceBoundary2D.h
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+/*  This file is part of the OpenLB library
+ *
+ *  Copyright (C) 2007 Orestis Malaspinas, Jonas Latt
+ *  E-mail contact: info@openlb.net
+ *  The most recent release of OpenLB can be downloaded at
+ *  <http://www.openlb.net/>
+ *
+ *  This program is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU General Public License
+ *  as published by the Free Software Foundation; either version 2
+ *  of the License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public
+ *  License along with this program; if not, write to the Free
+ *  Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA  02110-1301, USA.
+*/
+
+
+#ifndef EXTENDED_FINITE_DIFFERENCE_BOUNDARY_2D_H
+#define EXTENDED_FINITE_DIFFERENCE_BOUNDARY_2D_H
+
+#include "core/postProcessing.h"
+#include "momentaOnBoundaries.h"
+#include "core/blockLattice2D.h"
+#include "boundaryCondition2D.h"
+
+
+namespace olb {
+
+/**
+* This class computes the finite difference approximation to LB boundary conditions
+* on a flat wall in 2D with all the terms of the CE expansion. The details
+* on the computations can be found in the thesis of
+* Jonas Latt, "Hydrodynamic limit of lattice Boltzmann equations",
+* University of Geneva, (2007).
+*/
+template<typename T, typename DESCRIPTOR, int direction, int orientation>
+class ExtendedStraightFdBoundaryPostProcessor2D : public LocalPostProcessor2D<T,DESCRIPTOR> {
+public:
+  ExtendedStraightFdBoundaryPostProcessor2D(int x0_, int x1_, int y0_, int y1_);
+  int extent() const override
+  {
+    return 1;
+  }
+  int extent(int whichDirection) const override
+  {
+    return 1;
+  }
+  void process(BlockLattice2D<T,DESCRIPTOR>& blockLattice) override;
+  void processSubDomain(BlockLattice2D<T,DESCRIPTOR>& blockLattice,
+                                int x0_, int x1_, int y0_, int y1_ ) override;
+private:
+  template<int deriveDirection>
+  void interpolateGradients(BlockLattice2D<T,DESCRIPTOR> const& blockLattice,
+                            T velDeriv[DESCRIPTOR::d], int iX, int iY) const;
+  template<int deriveDirection>
+  void interpolateGradients (
+    BlockLattice2D<T,DESCRIPTOR> const& blockLattice,T& rhoDeriv,
+    int iX, int iY ) const;
+private:
+  int x0, x1, y0, y1;
+};
+
+template<typename T, typename DESCRIPTOR, int direction, int orientation>
+class ExtendedStraightFdBoundaryProcessorGenerator2D : public PostProcessorGenerator2D<T,DESCRIPTOR> {
+public:
+  ExtendedStraightFdBoundaryProcessorGenerator2D(int x0_, int x1_, int y0_, int y1_);
+  PostProcessor2D<T,DESCRIPTOR>* generate() const override;
+  PostProcessorGenerator2D<T,DESCRIPTOR>*  clone() const override;
+};
+
+
+////////// Factory function for Extended Finite Difference BC ///////////////////////////////
+
+template<typename T, typename DESCRIPTOR, typename MixinDynamics=BGKdynamics<T,DESCRIPTOR> >
+OnLatticeBoundaryCondition2D<T,DESCRIPTOR>*
+createExtendedFdBoundaryCondition2D(BlockLatticeStructure2D<T,DESCRIPTOR>& block);
+
+}  // namespace olb
+
+#endif