@article{PPN379157292+dmdlog11,
title = {\S\ 4. Trennungsaxiome: T0- und T1-R\"aume.},
booktitle = {Topologie Bd. 1},
series = {GDML\_Books},
year = {1935},
pages = {58},
url = {http://dml.mathdoc.fr/item/PPN379157292+dmdlog11}
}
(éd.). § 4. Trennungsaxiome: T0- und T1-Räume., dans Topologie Bd. 1, GDML_Books, (1935), p. 58. http://gdmltest.u-ga.fr/item/PPN379157292+dmdlog11/