@article{AMLG_1969__12_137823,
     author = {Franz v. Kutschera},
     title = {Ein verallgemeinerter {Widerlegungsbegriff} f\"ur {Gentzenkalk\"ule.}},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {104--118},
     publisher = {mathdoc},
     volume = {12},
     year = {1969},
     zbl = {0198.01304},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1969__12_137823/}
}