Reference solution
=====================

There is no reference solution for this problem. Non-regression tests are therefore carried out. We check that the :math:`\mathrm{XFEM}` tests give the same results as their :math:`\mathrm{FEM}` counterparts. As such, modeling :math:`D` is a reference for models :math:`E` to :math:`G`, modeling :math:`A` is a reference for modeling :math:`H` and modeling :math:`C` is a reference for models :math:`I` and :math:`J`.