@article{AM2_1978__18_136791,
     author = {Helmut Brass},
     title = {Umkehrs\"atze beim {Trapezverfahren.}},
     journal = {Aequationes mathematicae},
     pages = {338--344},
     year = {1978},
     volume = {18},
     zbl = {0405.65003},
     url = {http://geodesic.mathdoc.fr/item/AM2_1978__18_136791/}
}