@article{NUMA_1993__64_2_133718,
     author = {T.N.L. Patterson},
     title = {Modified optimal quadrature extensions.},
     journal = {Numerische Mathematik},
     pages = {511--520},
     publisher = {mathdoc},
     volume = {64},
     number = {2},
     year = {1993},
     zbl = {0801.65016},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1993__64_2_133718/}
}