diff --git a/src/base_def.h b/src/base_def.h
index efd7184..321b288 100644
--- a/src/base_def.h
+++ b/src/base_def.h
@@ -84,6 +84,10 @@ namespace MultiArrayTools
     // multi_array.h
     template <typename T, class Range>
     class MultiArrayBase;
+
+    // multi_array.h
+    template <typename T, class Range>
+    class MutableMultiArrayBase;
     
     // multi_array.h
     template <typename T, class Range>
diff --git a/src/multi_array.cc b/src/multi_array.cc
index a045264..b1f2e36 100644
--- a/src/multi_array.cc
+++ b/src/multi_array.cc
@@ -39,25 +39,11 @@ namespace MultiArrayTools
     }
 
     template <typename T, class Range>
-    template <class... NameTypes>
-    MultiArrayOperationRoot<T,Range> MultiArrayBase<T,Range>::operator()(const NameTypes&... str)
+    bool MultiArrayBase<T,Range>::isConst() const
     {
-	return MultiArrayOperationRoot<T,Range>(*this, Name("master", str...));
+	return true;
     }
-
-    template <typename T, class Range>
-    template <class NameType>
-    MultiArrayOperationRoot<T,Range> MultiArrayBase<T,Range>::operator()(const NameType& name, bool master)
-    {
-	//CHECK;
-	if(master){
-	    return MultiArrayOperationRoot<T,Range>(*this, name);
-	}
-	else {
-	    return operator()(name);
-	}
-    }
-
+    
     template <typename T, class Range>
     template <class... NameTypes>
     ConstMultiArrayOperationRoot<T,Range> MultiArrayBase<T,Range>::operator()(const NameTypes&... str) const
@@ -83,6 +69,40 @@ namespace MultiArrayTools
     {
 	return mInit;
     }
+
+    /******************************
+     *  MutableMultiArrayBase     *	     
+     ******************************/
+
+    template <typename T, class Range>
+    MutableMultiArrayBase<T,Range>::MutableMultiArrayBase(const Range& range) : MultiArrayBase<T,Range>(range) {}
+    
+    template <typename T, class Range>
+    bool MutableMultiArrayBase<T,Range>::isConst() const
+    {
+	return false;
+    }
+    
+    template <typename T, class Range>
+    template <class... NameTypes>
+    MultiArrayOperationRoot<T,Range> MutableMultiArrayBase<T,Range>::operator()(const NameTypes&... str)
+    {
+	return MultiArrayOperationRoot<T,Range>(*this, Name("master", str...));
+    }
+
+    template <typename T, class Range>
+    template <class NameType>
+    MultiArrayOperationRoot<T,Range> MutableMultiArrayBase<T,Range>::operator()(const NameType& name, bool master)
+    {
+	//CHECK;
+	if(master){
+	    return MultiArrayOperationRoot<T,Range>(*this, name);
+	}
+	else {
+	    return operator()(name);
+	}
+    }
+
     
     /*******************
      *  MultiArray     *	     
@@ -90,7 +110,7 @@ namespace MultiArrayTools
 
     template <typename T, class Range>
     MultiArray<T,Range>::MultiArray(const Range& range) :
-	MultiArrayBase<T,Range>(range),
+	MutableMultiArrayBase<T,Range>(range),
 	mCont(MAB::mRange->size())
     {
 	MAB::mInit = true;
@@ -98,7 +118,7 @@ namespace MultiArrayTools
 
     template <typename T, class Range>
     MultiArray<T,Range>::MultiArray(const Range& range, const std::vector<T>& vec) :
-	MultiArrayBase<T,Range>(range),
+	MutableMultiArrayBase<T,Range>(range),
 	mCont(vec)
     {
 	MAB::mInit = true;
@@ -109,7 +129,7 @@ namespace MultiArrayTools
     
     template <typename T, class Range>
     MultiArray<T,Range>::MultiArray(const Range& range, std::vector<T>&& vec) :
-	MultiArrayBase<T,Range>(range),
+	MutableMultiArrayBase<T,Range>(range),
 	mCont(vec)
     {
 	MAB::mInit = true;
@@ -121,7 +141,7 @@ namespace MultiArrayTools
     template <typename T, class Range>
     template <class Range2, class Range3>
     MultiArray<T,Range>::MultiArray(const MultiArray<MultiArray<T,Range2>,Range3> in) :
-	MultiArrayBase<T,Range>(merge(in.range(), in[ in.begin() ].range()))
+	MutableMultiArrayBase<T,Range>(merge(in.range(), in[ in.begin() ].range()))
 	// assert that Range2 has always same extension
     {
 	MAB::mInit = true;
diff --git a/src/multi_array.h b/src/multi_array.h
index 32eb447..62f5fa5 100644
--- a/src/multi_array.h
+++ b/src/multi_array.h
@@ -27,7 +27,6 @@ namespace MultiArrayTools
 
 	virtual ~MultiArrayBase() = default;
 	
-	virtual T& operator[](const typename Range::IndexType& i) = 0;
 	virtual const T& operator[](const typename Range::IndexType& i) const = 0;
 
 	virtual size_t size() const; 
@@ -38,14 +37,8 @@ namespace MultiArrayTools
 
 	virtual const Range& range() const;
 
-	virtual bool isConst() const = 0;
+	virtual bool isConst() const;
 	
-	template <class... NameTypes>
-	MultiArrayOperationRoot<T,Range> operator()(const NameTypes&... str);
-
-	template <class NameType>
-	MultiArrayOperationRoot<T,Range> operator()(const NameType& name, bool master);
-
 	template <class... NameTypes>
 	ConstMultiArrayOperationRoot<T,Range> operator()(const NameTypes&... str) const;
 
@@ -59,9 +52,31 @@ namespace MultiArrayTools
 	std::shared_ptr<Range> mRange;
 
     };
+
+    template <typename T, class Range>
+    class MutableMultiArrayBase : public MultiArrayBase<T,Range>
+    {
+    public:
+
+	// iterator ( containing idx of Range )
+	
+	DEFAULT_MEMBERS(MutableMultiArrayBase);
+	MutableMultiArrayBase(const Range& range);
+
+	virtual T& operator[](const typename Range::IndexType& i) = 0;
+
+	virtual bool isConst() const override;
+
+	template <class... NameTypes>
+	MultiArrayOperationRoot<T,Range> operator()(const NameTypes&... str);
+
+	template <class NameType>
+	MultiArrayOperationRoot<T,Range> operator()(const NameType& name, bool master);
+
+    };
     
     template <typename T, class Range>
-    class MultiArray : public MultiArrayBase<T,Range>
+    class MultiArray : public MutableMultiArrayBase<T,Range>
     {
     public:
 
diff --git a/src/multi_array_operation.cc b/src/multi_array_operation.cc
index a969fab..2bc20ff 100644
--- a/src/multi_array_operation.cc
+++ b/src/multi_array_operation.cc
@@ -75,7 +75,7 @@ namespace MultiArrayTools
     
     template <typename T, class Range>
     MultiArrayOperationRoot<T,Range>::
-    MultiArrayOperationRoot(MultiArrayBase<T,Range>& ma,
+    MultiArrayOperationRoot(MutableMultiArrayBase<T,Range>& ma,
 			    const Name& nm) :
 	MutableMultiArrayOperationBase<T>(),
 	mArrayRef(ma),
diff --git a/src/multi_array_operation.h b/src/multi_array_operation.h
index ff74c66..64c7ecc 100644
--- a/src/multi_array_operation.h
+++ b/src/multi_array_operation.h
@@ -51,7 +51,7 @@ namespace MultiArrayTools
 	typedef typename Range::IndexType IndexType;
 	//typedef decltype(MultiArray<T,Range>().begin()) IndexType;
 
-	MultiArrayOperationRoot(MultiArrayBase<T,Range>& ma, const Name& nm);
+	MultiArrayOperationRoot(MutableMultiArrayBase<T,Range>& ma, const Name& nm);
 	MultiArrayOperationRoot& operator=(const MultiArrayOperationRoot& in);
 
 	MultiArrayOperationRoot& operator=(MultiArrayOperationRoot& in);
@@ -138,7 +138,7 @@ namespace MultiArrayTools
 	template <class RangeX>
 	const MultiArrayOperationRoot& makeConstSlice(const MultiArrayOperationRoot<T,RangeX>& in);
 	
-	MultiArrayBase<T,Range>& mArrayRef;
+	MutableMultiArrayBase<T,Range>& mArrayRef;
 	mutable IndexType mIndex;
 	Name mNm;
     };
diff --git a/src/slice.cc b/src/slice.cc
index 9d07fc0..026cc0f 100644
--- a/src/slice.cc
+++ b/src/slice.cc
@@ -7,8 +7,21 @@ namespace MultiArrayTools
 
     template <typename T, class Range, class MARange>
     Slice<T,Range,MARange>::
-    Slice(const Range& range) :
-	MultiArrayBase<T,Range>(range) {}
+    Slice(const Range& range,
+	  MutableMultiArrayBase<T,MARange>& multiArrayRef,
+	  const Name& ownNm, // for correct linkage
+	  const typename MARange::IndexType& MAIdx, // for desired slice position
+	  const Name& MANm) :
+	MutableMultiArrayBase<T,Range>(range),
+	mOwnName(ownNm), mMAName(MANm), mMultiArrayPtr(&multiArrayRef),
+	mMAIdx(MAIdx)	
+    {
+	MAB::mInit = true;
+	mOwnIdx = MAB::mRange->begin();
+	mMAIdx.name(MANm);
+	mOwnIdx.name(ownNm);
+	mMAIdx.linkTo(&mOwnIdx);
+    }
 
     template <typename T, class Range, class MARange>
     bool Slice<T,Range,MARange>::isSlice() const
@@ -16,8 +29,9 @@ namespace MultiArrayTools
 	return true;
     }
 
+    /*
     template <typename T, class Range, class MARange>
-    void Slice<T,Range,MARange>::set(MultiArrayBase<T,MARange>& multiArrayRef,
+    void Slice<T,Range,MARange>::set(MutableMultiArrayBase<T,MARange>& multiArrayRef,
 				     const Name& ownNm, // for correct linkage
 				     const typename MARange::IndexType& MAIdx, // for desired slice position
 				     const Name& MANm) // for correct linkage)
@@ -32,7 +46,9 @@ namespace MultiArrayTools
 	mOwnIdx.name(ownNm);
 	mMAIdx.linkTo(&mOwnIdx);
     }
+    */
 
+    /*
     template <typename T, class Range, class MARange>
     void Slice<T,Range,MARange>::setConst(const MultiArrayBase<T,MARange>& multiArrayRef,
 					  const Name& ownNm, // for correct linkage
@@ -49,7 +65,7 @@ namespace MultiArrayTools
 	mOwnIdx.name(ownNm);
 	mMAIdx.linkTo(&mOwnIdx);
     }
-
+    */
     
     template <typename T, class Range, class MARange>
     auto Slice<T,Range,MARange>::begin() const -> decltype(Range().begin())
@@ -84,12 +100,32 @@ namespace MultiArrayTools
     {
 	return false;
     }
-    
+
+    /*
     template <typename T, class Range, class MARange>
     ConstSlice<T,Range,MARange>::
     ConstSlice(const Range& range) :
 	MultiArrayBase<T,Range>(range) {}
+    */
+    template <typename T, class Range, class MARange>
+    ConstSlice<T,Range,MARange>::
+    ConstSlice(const Range& range,
+	       const MultiArrayBase<T,MARange>& multiArrayRef,
+	       const Name& ownNm, // for correct linkage
+	       const typename MARange::IndexType& MAIdx, // for desired slice position
+	       const Name& MANm) :
+	MutableMultiArrayBase<T,Range>(range),
+	mMultiArrayPtr(&multiArrayRef),
+	mMAIdx(MAIdx)	
+    {
+	MAB::mInit = true;
+	mOwnIdx = MAB::mRange->begin();
+	mMAIdx.name(MANm);
+	mOwnIdx.name(ownNm);
+	mMAIdx.linkTo(&mOwnIdx);
+    }
 
+    
     template <typename T, class Range, class MARange>
     ConstSlice<T,Range,MARange>::
     ConstSlice(const Slice<T,Range,MARange>& slice) :
diff --git a/src/slice.h b/src/slice.h
index 7020ef3..b1ccac7 100644
--- a/src/slice.h
+++ b/src/slice.h
@@ -15,14 +15,18 @@ namespace MultiArrayTools
     // MARange = original range of multi array of which this is the slice
     // Index = index which determines the slice position (remnant of MARange w.o. Range)
     template <typename T, class Range, class MARange/*, class Index*/>
-    class Slice : public MultiArrayBase<T,Range> // yes, 'Range' is correct !!!
+    class Slice : public MutableMultiArrayBase<T,Range> // yes, 'Range' is correct !!!
     {
     public:
 
 	typedef MultiArrayBase<T,Range> MAB;
 
-	Slice(const Range& range);
-
+	Slice(const Range& range,
+	      MutableMultiArrayBase<T,MARange>& multiArrayRef,
+	      const Name& ownNm,
+	      const typename MARange::IndexType& MAIdx,
+	      const Name& MANm);
+		
 	virtual T& operator[](const typename Range::IndexType& i) override;
 	virtual const T& operator[](const typename Range::IndexType& i) const override;
 	
@@ -34,28 +38,28 @@ namespace MultiArrayTools
 
 	virtual bool isSlice() const override;
 	virtual bool isConst() const override;
-	
-	void set(MultiArrayBase<T,MARange>& multiArrayRef,
-		 const Name& ownNm,
-		 const typename MARange::IndexType& MAIdx,
-		 const Name& MANm);
 
+	/*
+	void set();
+	*/
+
+	/*
 	void setConst(const MultiArrayBase<T,MARange>& multiArrayRef,
 		      const Name& ownNm,
 		      const typename MARange::IndexType& MAIdx,
 		      const Name& MANm); 
-
+	*/
 	template <typename U, class RangeX, class MARangeX>	
 	friend class ConstSlice;
 	
     private:
 
-	MultiArrayBase<T,MARange> const* mConstMultiArrayPtr = nullptr;
-	MultiArrayBase<T,MARange>* mMultiArrayPtr = nullptr;
-	mutable typename Range::IndexType mOwnIdx;
-	mutable typename MARange::IndexType mMAIdx;
 	Name mOwnName;
 	Name mMAName;
+	MutableMultiArrayBase<T,MARange>* mMultiArrayPtr = nullptr;
+	mutable typename Range::IndexType mOwnIdx;
+	mutable typename MARange::IndexType mMAIdx;
+	
     };
 
     template <typename T, class Range, class MARange/*, class Index*/>
@@ -65,7 +69,12 @@ namespace MultiArrayTools
 
 	typedef MultiArrayBase<T,Range> MAB;
 
-	ConstSlice(const Range& range);
+	//ConstSlice(const Range& range);
+	ConstSlice(const Range& range,
+		   const MultiArrayBase<T,MARange>& multiArrayRef,
+		   const Name& ownNm,
+		   const typename MARange::IndexType& MAIdx,
+		   const Name& MANm);
 	ConstSlice(const Slice<T,Range,MARange>& slice);
 
 	virtual T& operator[](const typename Range::IndexType& i) override;
diff --git a/src/unit_test.cc b/src/unit_test.cc
index fb26b96..5f37bed 100644
--- a/src/unit_test.cc
+++ b/src/unit_test.cc
@@ -413,12 +413,20 @@ namespace {
 	auto i2 = i.template getIndex<1>();
 	auto i3 = i.template getIndex<2>();
 
-	Slice2d3dAny sl(ra);
-	sl("alpha","gamma") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 2, i3 = 0)];
+	Slice2d3dAny sl(ra, ma, MAT::Name("master", "alpha", "gamma"),
+			i(i1 = 0, i2 = 2, i3 = 0),
+			MAT::Name("master", "alpha","beta","gamma"));
+	
+	//Slice2d3dAny sl(ra);
+	//sl("alpha","gamma") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 2, i3 = 0)];
 	EXPECT_EQ(sl.size(), 6);
 
-	Slice2d3dAny sl2(rb);
-	sl2("alpha","beta") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 0, i3 = 1)];
+	Slice2d3dAny sl2(rb, ma, MAT::Name("master", "alpha", "beta"),
+			 i(i1 = 0, i2 = 0, i3 = 1),
+			 MAT::Name("master", "alpha","beta","gamma"));
+	
+	//Slice2d3dAny sl2(rb);
+	//sl2("alpha","beta") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 0, i3 = 1)];
 	EXPECT_EQ(sl2.size(), 12);
     }
 
@@ -428,8 +436,10 @@ namespace {
 	auto i1 = i.template getIndex<0>();
 	auto i2 = i.template getIndex<1>();
 	auto i3 = i.template getIndex<2>();
-	Slice2d3dAny sl(ra);
-	sl("alpha","gamma") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 2, i3 = 0)];
+	Slice2d3dAny sl(ra, ma, MAT::Name("master", "alpha", "gamma"),
+			i(i1 = 0, i2 = 2, i3 = 0),
+			MAT::Name("master", "alpha","beta","gamma"));
+	//sl("alpha","gamma") = ma("alpha","beta","gamma")[i(i1 = 0, i2 = 2, i3 = 0)];
 
 	auto j = sl.begin();
 	auto j1 = j.template getIndex<0>();