@article{MAN_1937__114_159934,
     author = {K. Stein},
     title = {Zur {Theorie} der {Funktionen} mehrerer komplexer {Ver\"anderlichen.} {Die} {Regularit\"atsh\"ullen} niederdimensionaler {Mannigfaltigkeiten}},
     journal = {Mathematische Annalen},
     pages = {543--569},
     publisher = {mathdoc},
     volume = {114},
     year = {1937},
     zbl = {0017.07405},
     url = {http://geodesic.mathdoc.fr/item/MAN_1937__114_159934/}
}