Rectangular covers of products missing diagonals
Yajima, Yukinobu
Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994), p. 147-153 / Harvested from Czech Digital Mathematics Library
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We give a characterization of a paracompact $\Sigma$-space to have a $G_\delta$-diagonal in terms of three rectangular covers of $X^2\setminus\Delta$. Moreover, we show that a local property and a global property of a space $X$ are given by the orthocompactness of $(X\times\beta X)\setminus\Delta$.

Publié le : 1994-01-01
Classification:  54B10,  54D20,  54E18 
@article{118648,
     author = {Yukinobu Yajima},
     title = {Rectangular covers of products missing diagonals},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     volume = {35},
     year = {1994},
     pages = {147-153},
     zbl = {0804.54010},
     mrnumber = {1292590},
     language = {en},
     url = {http://dml.mathdoc.fr/item/118648}
}

Yajima, Yukinobu. Rectangular covers of products missing diagonals. Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994) pp. 147-153. http://gdmltest.u-ga.fr/item/118648/

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