@article{AMLG_1985__25_138038,
     author = {E.G.K. L\'opez-Escobar},
     title = {K\"onig's {Lemma,} the ...-rule and primitive recursive arithmetic.},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {67--74},
     publisher = {mathdoc},
     volume = {25},
     year = {1985},
     zbl = {0594.03036},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1985__25_138038/}
}