@article{2197,
author = {M\"uller, Gert H.},
title = {?ber die Eigenschaften der Teilmengen eines Kuratowski'schen Raumes - I},
journal = {Portugaliae mathematica},
volume = {9},
year = {1950},
pages = {149-167},
zbl = {0039.39302},
mrnumber = {0038641},
language = {de},
url = {http://dml.mathdoc.fr/item/2197}
}
Müller, Gert H. �?ber die Eigenschaften der Teilmengen eines Kuratowski'schen Raumes - I. Portugaliae mathematica, Tome 9 (1950) pp. 149-167. http://gdmltest.u-ga.fr/item/2197/