@article{MAN_1956__132_160525,
     author = {R. Harrop},
     title = {On {Disjunctions} and {Existential} {Statements} in {Intuitionistic} {Systems} of {Logic.}},
     journal = {Mathematische Annalen},
     pages = {347--361},
     publisher = {mathdoc},
     volume = {132},
     year = {1956},
     zbl = {0071.24504},
     url = {http://geodesic.mathdoc.fr/item/MAN_1956__132_160525/}
}