We give sufficient and necessary conditions to be fulfilled by a filter $\Psi $ and an ideal $\Lambda $ in order that the $\Psi $-quotient space of the $\Lambda $-ideal product space preserves $T_k$-properties ($k=0,1,2,3,3\frac{1}{2}$) (``in the sense of the \L os theorem''). Tychonoff products, box products and ultraproducts appear as special cases of the general construction.
@article{118543,
author = {Milan Z. Grulovi\'c and Milo\v s S. Kurili\'c},
title = {On the preservation of separation axioms in products},
journal = {Commentationes Mathematicae Universitatis Carolinae},
volume = {33},
year = {1992},
pages = {713-721},
zbl = {0786.54009},
mrnumber = {1240193},
language = {en},
url = {http://dml.mathdoc.fr/item/118543}
}
Grulović, Milan Z.; Kurilić, Miloš S. On the preservation of separation axioms in products. Commentationes Mathematicae Universitatis Carolinae, Tome 33 (1992) pp. 713-721. http://gdmltest.u-ga.fr/item/118543/
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