Visualising higher-order elements

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I am interested in visualising the solution of higher-order elements, particularly cubic elements, using the vtkHigherOrderTriangle and vtkHigherOrderTetra objects.
I tried the following, similar to what I have done with the linear and quadratic elements. But, with the higher-order elements, the code does not compile.
vtkSmartPointer triaHigherVTK = vtkSmartPointer::New();
vtkSmartPointer quadHigherVTK = vtkSmartPointer::New();

Also cannot create an object using the following since it is an abstract class type.
vtkHigherOrderTriangle triaHigherVTK;

I could not find any tutorials on these. I would appreciate any help in using these classes for exporting unstructured grid data.