Gaspar, F. J., F. J. Lisbona, and C. Rodrigo. “Multigrid Fourier Analysis on semi‐structured Anisotropic Meshes for Vector Problems”. Mathematical Modelling and Analysis, vol. 15, no. 1, Feb. 2010, pp. 39-54, doi:10.3846/1392-6292.2010.15.39-54.