@article{MAN_1949__121_160181,
     author = {Helmut Wielandt},
     title = {Die {Einschlie{\ss}ung} von {Eigenwerten} normaler {Matrizen}},
     journal = {Mathematische Annalen},
     pages = {234--241},
     year = {1949},
     volume = {121},
     zbl = {0034.15702},
     url = {http://geodesic.mathdoc.fr/item/MAN_1949__121_160181/}
}