§ 192. Polygonscharen
Lehrbuch der Algebra Bd. 3, GDML_Books, (1908), p. 672 / Harvested from
Access to full text 
@article{PPN234736674+dmdlog230,
     title = {\S\ 192. Polygonscharen},
     booktitle = {Lehrbuch der Algebra Bd. 3},
     series = {GDML\_Books},
     year = {1908},
     pages = {672},
     url = {http://dml.mathdoc.fr/item/PPN234736674+dmdlog230}
}

 (éd.). § 192. Polygonscharen, dans Lehrbuch der Algebra Bd. 3, GDML_Books,  (1908), p. 672. http://gdmltest.u-ga.fr/item/PPN234736674+dmdlog230/