diff --git a/Src/Kernels/Interpolation/FInterpCell.hpp b/Src/Kernels/Interpolation/FInterpCell.hpp
new file mode 100644
index 0000000000000000000000000000000000000000..8b49b297b2f8ba7ba06973f957a1d00c57480ae1
--- /dev/null
+++ b/Src/Kernels/Interpolation/FInterpCell.hpp
@@ -0,0 +1,199 @@
+// ===================================================================================
+// Copyright ScalFmm 2011 INRIA, Olivier Coulaud, Bérenger Bramas, Matthias Messner
+// olivier.coulaud@inria.fr, berenger.bramas@inria.fr
+// This software is a computer program whose purpose is to compute the FMM.
+//
+// This software is governed by the CeCILL-C and LGPL licenses and
+// abiding by the rules of distribution of free software.
+//
+// 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 and CeCILL-C Licenses for more details.
+// "http://www.cecill.info".
+// "http://www.gnu.org/licenses".
+// ===================================================================================
+#ifndef FINTERPCELL_HPP
+#define FINTERPCELL_HPP
+
+
+#include "../../Extensions/FExtendMortonIndex.hpp"
+#include "../../Extensions/FExtendCoordinate.hpp"
+
+#include "./FInterpTensor.hpp"
+#include "../../Components/FBasicCell.hpp"
+#include "../../Extensions/FExtendCellType.hpp"
+
+#include "../../Utils/FComplexe.hpp"
+
+/**
+ * @author Pierre Blanchard (pierre.blanchard@inria.fr)
+ * @class FInterpCell
+ * Please read the license
+ *
+ * This class defines a cell that can be used in both Chebyshev and 
+ * Lagrange based FMM.
+ * 
+ * PB: This class provides the storage and accessors for the transformed 
+ * expansion used in the Uniform FMM (in Fourier space, i.e. complex valued).
+ *
+ * PB: Beware! This class does not support yet the storage of the compressed 
+ * expansions used in the low rank version of the Chebyshev FMM algorithm.
+ *
+ * @param NVALS is the number of right hand side.
+ */
+template <int ORDER, int NRHS = 1, int NLHS = 1, int NVALS = 1>
+class FInterpCell : public FBasicCell
+{
+  static const int VectorSize = TensorTraits<ORDER>::nnodes;
+  static const int TransformedVectorSize = (2*ORDER-1)*(2*ORDER-1)*(2*ORDER-1);
+
+  FReal multipole_exp[NRHS * NVALS * VectorSize]; //< Multipole expansion
+  FReal     local_exp[NLHS * NVALS * VectorSize]; //< Local expansion
+  // PB: Store multipole and local expansion in Fourier space
+  FComplexe transformed_multipole_exp[NRHS * NVALS * TransformedVectorSize];
+  FComplexe     transformed_local_exp[NLHS * NVALS * TransformedVectorSize];
+
+public:
+  FInterpCell(){
+    memset(multipole_exp, 0, sizeof(FReal) * NRHS * NVALS * VectorSize);
+    memset(local_exp, 0, sizeof(FReal) * NLHS * NVALS * VectorSize);
+    memset(transformed_multipole_exp, 0, 
+           sizeof(FComplexe) * NRHS * NVALS * TransformedVectorSize);
+    memset(transformed_local_exp, 0, 
+           sizeof(FComplexe) * NLHS * NVALS * TransformedVectorSize);
+  }
+
+  ~FInterpCell() {}
+
+  /** Get Multipole */
+  const FReal* getMultipole(const int inRhs) const
+  {	return this->multipole_exp + inRhs*VectorSize;
+  }
+  /** Get Local */
+  const FReal* getLocal(const int inRhs) const{
+    return this->local_exp + inRhs*VectorSize;
+  }
+
+  /** Get Multipole */
+  FReal* getMultipole(const int inRhs){
+    return this->multipole_exp + inRhs*VectorSize;
+  }
+  /** Get Local */
+  FReal* getLocal(const int inRhs){
+    return this->local_exp + inRhs*VectorSize;
+  }
+
+  /** To get the leading dim of a vec */
+  int getVectorSize() const{
+    return VectorSize;
+  }
+
+  /** Get Transformed Multipole */
+  const FComplexe* getTransformedMultipole(const int inRhs) const{	
+    return this->transformed_multipole_exp + inRhs*TransformedVectorSize;
+  }
+  /** Get Transformed Local */
+  const FComplexe* getTransformedLocal(const int inRhs) const{
+    return this->transformed_local_exp + inRhs*TransformedVectorSize;
+  }
+
+  /** Get Transformed Multipole */
+  FComplexe* getTransformedMultipole(const int inRhs){
+    return this->transformed_multipole_exp + inRhs*TransformedVectorSize;
+  }
+  /** Get Transformed Local */
+  FComplexe* getTransformedLocal(const int inRhs){
+    return this->transformed_local_exp + inRhs*TransformedVectorSize;
+  }
+
+  /** To get the leading dim of a vec */
+  int getTransformedVectorSize() const{
+    return TransformedVectorSize;
+  }
+
+  /** Make it like the begining */
+  void resetToInitialState(){
+    memset(multipole_exp, 0, sizeof(FReal) * NRHS * NVALS * VectorSize);
+    memset(local_exp, 0, sizeof(FReal) * NLHS * NVALS * VectorSize);
+    memset(transformed_multipole_exp, 0, 
+           sizeof(FComplexe) * NRHS * NVALS * TransformedVectorSize);
+    memset(transformed_local_exp, 0, 
+           sizeof(FComplexe) * NLHS * NVALS * TransformedVectorSize);
+  }
+
+  ///////////////////////////////////////////////////////
+  // to extend FAbstractSendable
+  ///////////////////////////////////////////////////////
+  template <class BufferWriterClass>
+  void serializeUp(BufferWriterClass& buffer) const{
+    buffer.write(multipole_exp, VectorSize*NVALS*NRHS);
+    buffer.write(transformed_multipole_exp, TransformedVectorSize*NVALS*NRHS);
+  }
+
+  template <class BufferReaderClass>
+  void deserializeUp(BufferReaderClass& buffer){
+    buffer.fillArray(multipole_exp, VectorSize*NVALS*NRHS);
+    buffer.fillArray(transformed_multipole_exp, TransformedVectorSize*NVALS*NRHS);
+  }
+  
+  template <class BufferWriterClass>
+  void serializeDown(BufferWriterClass& buffer) const{
+    buffer.write(local_exp, VectorSize*NVALS*NLHS);
+    buffer.write(transformed_local_exp, TransformedVectorSize*NVALS*NLHS);
+  }
+  
+  template <class BufferReaderClass>
+  void deserializeDown(BufferReaderClass& buffer){
+    buffer.fillArray(local_exp, VectorSize*NVALS*NLHS);
+    buffer.fillArray(transformed_local_exp, TransformedVectorSize*NVALS*NLHS);
+  }
+  
+  ///////////////////////////////////////////////////////
+  // to extend Serializable
+  ///////////////////////////////////////////////////////
+  template <class BufferWriterClass>
+  void save(BufferWriterClass& buffer) const{
+    FBasicCell::save(buffer);
+    buffer.write(multipole_exp, VectorSize*NVALS*NRHS);
+    buffer.write(transformed_multipole_exp, TransformedVectorSize*NVALS*NRHS);
+    buffer.write(local_exp, VectorSize*NVALS*NLHS);
+    buffer.write(transformed_local_exp, TransformedVectorSize*NVALS*NLHS);
+  }
+  
+  template <class BufferReaderClass>
+  void restore(BufferReaderClass& buffer){
+    FBasicCell::restore(buffer);
+    buffer.fillArray(multipole_exp, VectorSize*NVALS*NRHS);
+    buffer.fillArray(transformed_multipole_exp, TransformedVectorSize*NVALS*NRHS);
+    buffer.fillArray(local_exp, VectorSize*NVALS*NLHS);
+    buffer.fillArray(transformed_local_exp, TransformedVectorSize*NVALS*NLHS);
+  }
+  
+  static constexpr int GetSize(){
+    return (NRHS+NLHS)*NVALS*VectorSize * (int) sizeof(FReal) + (NRHS+NLHS)*NVALS*TransformedVectorSize * (int) sizeof(FComplexe);
+  }
+
+
+};
+
+template <int ORDER, int NRHS = 1, int NLHS = 1, int NVALS = 1>
+class FTypedInterpCell : public FInterpCell<ORDER,NRHS,NLHS,NVALS>, public FExtendCellType {
+public:
+  template <class BufferWriterClass>
+  void save(BufferWriterClass& buffer) const{
+    FInterpCell<ORDER,NRHS,NLHS,NVALS>::save(buffer);
+    FExtendCellType::save(buffer);
+  }
+  template <class BufferReaderClass>
+  void restore(BufferReaderClass& buffer){
+    FInterpCell<ORDER,NRHS,NLHS,NVALS>::restore(buffer);
+    FExtendCellType::restore(buffer);
+  }
+  void resetToInitialState(){
+    FInterpCell<ORDER,NRHS,NLHS,NVALS>::resetToInitialState();
+    FExtendCellType::resetToInitialState();
+  }
+};
+
+#endif //FINTERPCELL_HPP
diff --git a/Src/Kernels/Uniform/FUnifTensorialKernel.hpp b/Src/Kernels/Uniform/FUnifTensorialKernel.hpp
index 8d1aa343ba3aa175d1cebe58b8e0d9efdfb9e84d..0fec0f458bb8e4bf71ee41d7dc24228831312cbf 100644
--- a/Src/Kernels/Uniform/FUnifTensorialKernel.hpp
+++ b/Src/Kernels/Uniform/FUnifTensorialKernel.hpp
@@ -154,6 +154,7 @@ public:
 
     for(int idxV = 0 ; idxV < NVALS ; ++idxV){
       for (int idxLhs=0; idxLhs < nLhs; ++idxLhs){
+
           // update local index
           const int idxLoc = idxV*nLhs + idxLhs;
 
@@ -162,6 +163,7 @@ public:
 
           // update idxRhs
           const int idxRhs = idxLhs % nPV; 
+
           // update multipole index
           const int idxMul = idxV*nRhs + idxRhs;
 
@@ -169,18 +171,15 @@ public:
           const unsigned int d 
             = AbstractBaseClass::MatrixKernel.getPtr()->getPosition(idxLhs);
 
-//          std::cout<<"idxLhs="<< idxLhs 
-//                   <<" - d="<< d
-//                   <<" - idxRhs="<< idxRhs <<std::endl;
-
           for (int idx=0; idx<343; ++idx){
             if (SourceCells[idx]){
+
               M2LHandler->applyFC(idx, TreeLevel, scale, d,
                                   SourceCells[idx]->getTransformedMultipole(idxMul),
                                   TransformedLocalExpansion);
 
+            }
           }
-        }
       }// NLHS=NPOT*NPV
     }// NVALS
   }
diff --git a/Src/Kernels/Uniform/FUnifTensorialM2LHandler.hpp b/Src/Kernels/Uniform/FUnifTensorialM2LHandler.hpp
index 68f8291f329b651efc8eb3bda3b1ce611aa2165e..c1d1d2461b7367070bebce8dc72ac6deb8dae912 100644
--- a/Src/Kernels/Uniform/FUnifTensorialM2LHandler.hpp
+++ b/Src/Kernels/Uniform/FUnifTensorialM2LHandler.hpp
@@ -307,16 +307,13 @@ public:
                const FReal scale, const unsigned int d,
                const FComplexe *const FY, FComplexe *const FX) const
   {
-
-    FComplexe tmpFX; 
-
     // Perform entrywise product manually
     for (unsigned int j=0; j<opt_rc; ++j){
-      tmpFX=FC[d][idx*opt_rc + j];
-      tmpFX*=FY[j];
-      tmpFX*=scale;
-      FX[j]+=tmpFX;
+      FX[j].addMul(FComplexe(FC[d][idx*opt_rc + j].getReal()*scale,
+                             FC[d][idx*opt_rc + j].getImag()*scale), 
+                   FY[j]);
     }
+    
 
 //    // Perform entrywise product using BLAS and MKL routines
 //    // PB: not necessary faster than the naive version
@@ -492,14 +489,9 @@ public:
                const FReal, const unsigned int d,
                const FComplexe *const FY, FComplexe *const FX) const
   {
-
-    FComplexe tmpFX; 
-
     // Perform entrywise product manually
     for (unsigned int j=0; j<opt_rc; ++j){
-      tmpFX=FC[TreeLevel][d][idx*opt_rc + j];
-      tmpFX*=FY[j];
-      FX[j]+=tmpFX;
+      FX[j].addMul(FC[TreeLevel][d][idx*opt_rc + j], FY[j]);
     }
 
 //    // Perform entrywise product using BLAS and MKL routines