diff --git a/src/multi_array_operation.cc b/src/multi_array_operation.cc
index fb9c25a..bf571f5 100644
--- a/src/multi_array_operation.cc
+++ b/src/multi_array_operation.cc
@@ -188,8 +188,8 @@ namespace MultiArrayTools
     MultiArrayContraction<T,ContractOperation,Range2,MultiArrayOperationRoot<T,Range>,MAOps...>
     MultiArrayOperationRoot<T,Range>::contract(const ContractOperation& cop,
 					       const std::string& indexName,
-					       const typename Range2::IndexType& begin,
-					       const typename Range2::IndexType& end,
+					       size_t begin,
+					       size_t end,
 					       const MAOps&... mao) const
     {
 	//typename Range2::IndexType ind;
@@ -465,8 +465,8 @@ namespace MultiArrayTools
     MultiArrayContraction<T,ContractOperation,Range2,ConstMultiArrayOperationRoot<T,Range>,MAOps...>
     ConstMultiArrayOperationRoot<T,Range>::contract(const ContractOperation& cop,
 						    const std::string& indexName,
-						    const typename Range2::IndexType& begin,
-						    const typename Range2::IndexType& end,
+						    size_t begin,
+						    size_t end,
 						    const MAOps&... mao) const
     {
 	typename Range2::IndexType* ind = dynamic_cast<typename Range2::IndexType*>( mIndex.getLinked(indexName) );
@@ -767,13 +767,15 @@ namespace MultiArrayTools
     MultiArrayContraction<T,ContractOperation,Range,MAOps...>::
     MultiArrayContraction(const ContractOperation& cop,
 			  const typename Range::IndexType& runIndex,
-			  const typename Range::IndexType& beginIndex,
-			  const typename Range::IndexType& endIndex,
+			  size_t begin,
+			  size_t end,
 			  const MAOps&... mao) :
 	MultiArrayOperation<T,ContractOperation,MAOps...>(cop, mao...),
-	mBeginIndex(beginIndex), mEndIndex(endIndex),
+	mBeginIndex(runIndex), mEndIndex(runIndex),
 	mRunIndex(runIndex)
     {
+	mBeginIndex.setPos(begin);
+	mEndIndex.setPos(end);
 	MAO::linkIndicesTo(&mRunIndex);
     }
 
diff --git a/src/multi_array_operation.h b/src/multi_array_operation.h
index 3cf184a..360fee9 100644
--- a/src/multi_array_operation.h
+++ b/src/multi_array_operation.h
@@ -82,8 +82,8 @@ namespace MultiArrayTools
 	template <class Range2, class ContractOperation, class... MAOps>
 	MultiArrayContraction<T,ContractOperation,Range2,MultiArrayOperationRoot<T,Range>, MAOps...>
 	contract(const ContractOperation& cop, const std::string& indexName,
-		 const typename Range2::IndexType& begin,
-		 const typename Range2::IndexType& end,
+		 size_t begin,
+		 size_t end,
 		 const MAOps&... mao) const;
 
 	
@@ -181,8 +181,8 @@ namespace MultiArrayTools
 	template <class Range2, class ContractOperation, class... MAOps>
 	MultiArrayContraction<T,ContractOperation,Range2,ConstMultiArrayOperationRoot<T,Range>, MAOps...>
 	contract(const ContractOperation& cop, const std::string& indexName,
-		 const typename Range2::IndexType& begin,
-		 const typename Range2::IndexType& end,
+		 size_t begin,
+		 size_t end,
 		 const MAOps&... mao) const;
 	
 	template <class MAOp>
@@ -310,8 +310,8 @@ namespace MultiArrayTools
 	
 	MultiArrayContraction(const ContractOperation& cop,
 			      const typename Range::IndexType& runIndex,
-			      const typename Range::IndexType& beginIndex,
-			      const typename Range::IndexType& endIndex,
+			      size_t begin,
+			      size_t end,
 			      const MAOps&... mao);
 	
 	virtual const T& get() const override;