@article{MZ_1978__158_172627,
     author = {Niels Schwartz},
     title = {...-Strukturen.},
     journal = {Mathematische Zeitschrift},
     pages = {147--156},
     publisher = {mathdoc},
     volume = {158},
     year = {1978},
     language = {de},
     url = {http://geodesic.mathdoc.fr/item/MZ_1978__158_172627/}
}