@article{AMLG_1950__1_137716,
     author = {Y. Bar-Hillel},
     title = {Bolzano's propositional {Logic.}},
     journal = {Archiv f\"ur mathematische Logik und Grundlagenforschung},
     pages = {65--98},
     publisher = {mathdoc},
     volume = {1},
     year = {1950},
     zbl = {0047.01201},
     url = {http://geodesic.mathdoc.fr/item/AMLG_1950__1_137716/}
}