@article{AMLG_1980__20_137960,
     author = {Gerhard J\"ager},
     title = {Beweistheorie von {KPN.}},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {53--64},
     publisher = {mathdoc},
     volume = {20},
     year = {1980},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1980__20_137960/}
}