@article{MZ_1951__55_169239,
     author = {Hans-Georg Knoche},
     title = {\"Uber den {Frobenius'schen} {Klassenbegriff} in nilpotenten {Gruppen.}},
     journal = {Mathematische Zeitschrift},
     pages = {71--83},
     publisher = {mathdoc},
     volume = {55},
     year = {1951},
     zbl = {0043.25804},
     url = {http://geodesic.mathdoc.fr/item/MZ_1951__55_169239/}
}