@article{MZ_1954__60_169411,
     author = {Paul Lorenzen},
     title = {\"Uber die {Korrespondenzen} einer {Struktur.}},
     journal = {Mathematische Zeitschrift},
     pages = {61--65},
     publisher = {mathdoc},
     volume = {60},
     year = {1954},
     zbl = {0055.02302},
     url = {http://geodesic.mathdoc.fr/item/MZ_1954__60_169411/}
}