@article{NUMA_1971__18_132116,
     author = {O. H\"ubner},
     title = {Zweiparametrige {\"Uberrelaxation.}},
     journal = {Numerische Mathematik},
     pages = {354--366},
     publisher = {mathdoc},
     volume = {18},
     year = {1971},
     url = {http://geodesic.mathdoc.fr/item/NUMA_1971__18_132116/}
}