§. 129. Contragrediente Gruppen
Lehrbuch der Algebra Bd. 2, GDML_Books, (1896), p. 478 / Harvested from
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@article{PPN234735015+dmdlog154,
     title = {\S . 129. Contragrediente Gruppen},
     booktitle = {Lehrbuch der Algebra Bd. 2},
     series = {GDML\_Books},
     year = {1896},
     pages = {478},
     url = {http://dml.mathdoc.fr/item/PPN234735015+dmdlog154}
}

 (éd.). §. 129. Contragrediente Gruppen, dans Lehrbuch der Algebra Bd. 2, GDML_Books,  (1896), p. 478. http://gdmltest.u-ga.fr/item/PPN234735015+dmdlog154/