@article{NUMA_1990__57_6-7_133472,
     author = {Larry L. Schumaker and Peter Alfeld},
     title = {On the {Dimension} of {Bivariate} {Spline} {Spaces} of {Smoothness} r and {Degree} d = 3r + 1.},
     journal = {Numerische Mathematik},
     pages = {651--662},
     publisher = {mathdoc},
     volume = {57},
     number = {6-7},
     year = {1990},
     zbl = {0725.41012},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1990__57_6-7_133472/}
}