81. Die Materie.
Das Weltsystem Theil 2, GDML_Books, (1896), p. 41 / Harvested from
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@article{PPN517627655+dmdlog20,
     title = {81. Die Materie.},
     booktitle = {Das Weltsystem Theil 2},
     series = {GDML\_Books},
     year = {1896},
     pages = {41},
     url = {http://dml.mathdoc.fr/item/PPN517627655+dmdlog20}
}

 (éd.). 81. Die Materie., dans Das Weltsystem Theil 2, GDML_Books,  (1896), p. 41. http://gdmltest.u-ga.fr/item/PPN517627655+dmdlog20/