A strengthening of the Katětov-Tong insertion theorem
Kubiak, Tomasz
Commentationes Mathematicae Universitatis Carolinae, Tome 34 (1993), p. 357-362 / Harvested from Czech Digital Mathematics Library
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Normal spaces are characterized in terms of an insertion type theorem, which implies the Katětov-Tong theorem. The proof actually provides a simple necessary and sufficient condition for the insertion of an ordered pair of lower and upper semicontinuous functions between two comparable real-valued functions. As a consequence of the latter, we obtain a characterization of completely normal spaces by real-valued functions.

Publié le : 1993-01-01
Classification:  54C30,  54D15 
@article{118588,
     author = {Tomasz Kubiak},
     title = {A strengthening of the Kat\v etov-Tong insertion theorem},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {34},
     year = {1993},
     pages = {357-362},
     zbl = {0807.54023},
     mrnumber = {1241744},
     language = {en},
     url = {http://dml.mathdoc.fr/item/118588}
}

Kubiak, Tomasz. A strengthening of the Katětov-Tong insertion theorem. Commentationes Mathematicae Universitatis Carolinae, Tome 34 (1993) pp. 357-362. http://gdmltest.u-ga.fr/item/118588/

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