@article{AMLG_1962__6_137759,
     author = {Arnold Oberschelp},
     title = {Eine {Bemerkung} \"uber den {Kalk\"ul} des nat\"urlichen {Schlie{\ss}ens.}},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {3--6},
     publisher = {mathdoc},
     volume = {6},
     year = {1962},
     zbl = {0112.00505},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1962__6_137759/}
}