A Note Related to a Paper of Noiri
Publications de l'Institut Mathématique, _N_S_36 (1984) no. 50, p. 103
Voir la notice de l'article provenant de la source eLibrary of Mathematical Institute of the Serbian Academy of Sciences and Arts
In [4] Noiri gave a counterexample to Lemma 1.1 in [1] which
reads: If $f:X\to Y$ is an almost closed and almost continuous mapping,
then $f^{-1}(V)$ is regularly open (regularly closed) in $X$ for each
regularly open (regularly closed) set $V$ in $Y$. In this
counterexample $f$ is not a surjection. There exists also another
counterexample, where $f$ is a surjection. There exists also another
counterexample, where $f$ is a surjection (Example 1 in [2]). But,
Lemma A is necessarily true if a new condition is added.
@article{PIM_1984_N_S_36_50_a14,
author = {Ilija Kova\v{c}evi\'c},
title = {A {Note} {Related} to a {Paper} of {Noiri}},
journal = {Publications de l'Institut Math\'ematique},
pages = {103 },
publisher = {mathdoc},
volume = {_N_S_36},
number = {50},
year = {1984},
language = {en},
url = {http://geodesic.mathdoc.fr/item/PIM_1984_N_S_36_50_a14/}
}
Ilija Kovačević. A Note Related to a Paper of Noiri. Publications de l'Institut Mathématique, _N_S_36 (1984) no. 50, p. 103 . http://geodesic.mathdoc.fr/item/PIM_1984_N_S_36_50_a14/