@article{NUMA_1979__33_132631,
     author = {P.W. Smith and D.L. Barrow},
     title = {Efficient {L2} {Approximation} by {Splines.}},
     journal = {Numerische Mathematik},
     pages = {101--114},
     publisher = {mathdoc},
     volume = {33},
     year = {1979},
     zbl = {0442.41015},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1979__33_132631/}
}