§ 2. Topologische Räume.
Topologie Bd. 1, GDML_Books, (1935), p. 37 / Harvested from
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@article{PPN379157292+dmdlog9,
     title = {\S\ 2. Topologische R\"aume.},
     booktitle = {Topologie Bd. 1},
     series = {GDML\_Books},
     year = {1935},
     pages = {37},
     url = {http://dml.mathdoc.fr/item/PPN379157292+dmdlog9}
}

 (éd.). § 2. Topologische Räume., dans Topologie Bd. 1, GDML_Books,  (1935), p. 37. http://gdmltest.u-ga.fr/item/PPN379157292+dmdlog9/