  We apply the nonconforming discretisation of Wu and Xu (2019) to the
tri-Helmholtz equation on the plane where the source term is a functional
evaluating the test function on a one-dimensional mesh-aligned embedded curve.
We present error analysis for the convergence of the discretisation and linear
convergence as a function of mesh size is recovered almost everywhere away from
the embedded curve which aligns with classic regularity theory.
