W. Liu and J. Cui, “Anisotropic Quasi-Wilson Element with Conforming Finite Element Approximation for Coupled Continuum Pipe-Flow/Darcy Model in Karst Aquifers”, MMA, vol. 21, no. 4, pp. 431–449, Jun. 2016, doi: 10.3846/13926292.2016.1175388.