@article{PPN234735015+dmdlog10, title = {\S . l. Definition der Gruppen}, booktitle = {Lehrbuch der Algebra Bd. 2}, series = {GDML\_Books}, year = {1896}, pages = {3}, url = {http://dml.mathdoc.fr/item/PPN234735015+dmdlog10} }
(éd.). §. l. Definition der Gruppen, dans Lehrbuch der Algebra Bd. 2, GDML_Books, (1896), p. 3. http://gdmltest.u-ga.fr/item/PPN234735015+dmdlog10/