diff --git a/include/itkPhaseCorrelationImageRegistrationMethod.hxx b/include/itkPhaseCorrelationImageRegistrationMethod.hxx
index 507f4db..3a871a1 100644
--- a/include/itkPhaseCorrelationImageRegistrationMethod.hxx
+++ b/include/itkPhaseCorrelationImageRegistrationMethod.hxx
@@ -207,8 +207,9 @@ PhaseCorrelationImageRegistrationMethod<TFixedImage, TMovingImage, TInternalPixe
 
 
 template <typename TFixedImage, typename TMovingImage, typename TInternalPixelType>
-typename PhaseCorrelationImageRegistrationMethod<TFixedImage, TMovingImage, TInternalPixelType>::SizeType
+auto
 PhaseCorrelationImageRegistrationMethod<TFixedImage, TMovingImage, TInternalPixelType>::RoundUpToFFTSize(SizeType size)
+  -> SizeType
 {
   // FFTs are faster when image size can be factorized using smaller prime numbers
   const auto sizeGreatestPrimeFactor = std::min<SizeValueType>(5, m_FixedFFT->GetSizeGreatestPrimeFactor());
diff --git a/include/itkTileMontage.hxx b/include/itkTileMontage.hxx
index b987d11..cdf00ff 100644
--- a/include/itkTileMontage.hxx
+++ b/include/itkTileMontage.hxx
@@ -176,8 +176,8 @@ TileMontage<TImageType, TCoordinate>::GetImageHelper(TileIndexType nDIndex, bool
 }
 
 template <typename TImageType, typename TCoordinate>
-typename TileMontage<TImageType, TCoordinate>::ImageType::Pointer
-TileMontage<TImageType, TCoordinate>::GetImage(TileIndexType nDIndex, bool metadataOnly)
+auto
+TileMontage<TImageType, TCoordinate>::GetImage(TileIndexType nDIndex, bool metadataOnly) -> typename ImageType::Pointer
 {
   RegionType                  reg0; // default-initialized to zeroes
   SizeValueType               linearIndex = this->nDIndexToLinearIndex(nDIndex);
@@ -213,8 +213,9 @@ TileMontage<TImageType, TCoordinate>::nDIndexToLinearIndex(TileIndexType nDIndex
 }
 
 template <typename TImageType, typename TCoordinate>
-typename TileMontage<TImageType, TCoordinate>::TileIndexType
+auto
 TileMontage<TImageType, TCoordinate>::LinearIndexTonDIndex(DataObject::DataObjectPointerArraySizeType linearIndex) const
+  -> TileIndexType
 {
   TileIndexType ind;
   SizeValueType stride = 1u;