@article{NUMA_1972__20_132171,
     author = {Gerhard Schmei{\ss}er},
     title = {Optimale {Quadraturformeln} mit semidefiniten {Kernen.}},
     journal = {Numerische Mathematik},
     pages = {32--53},
     publisher = {mathdoc},
     volume = {20},
     year = {1972},
     zbl = {0238.65008},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1972__20_132171/}
}