| Title: | Rectangular covers of products missing diagonals (English) | 
| Author: | Yajima, Yukinobu | 
| Language: | English | 
| Journal: | Commentationes Mathematicae Universitatis Carolinae | 
| ISSN: | 0010-2628 (print) | 
| ISSN: | 1213-7243 (online) | 
| Volume: | 35 | 
| Issue: | 1 | 
| Year: | 1994 | 
| Pages: | 147-153 | 
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| Category: | math | 
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| Summary: | 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 $(X\times\beta X)\setminus\Delta$. (English) | 
| Keyword: | $\Sigma$-space | 
| Keyword: | $G_\delta$-diagonal | 
| Keyword: | $\sigma$-closure-preserving | 
| Keyword: | $\sigma$-cushioned | 
| Keyword: | rectangular cover | 
| Keyword: | \newline orthocompact | 
| Keyword: | metacompact | 
| Keyword: | Fréchet space | 
| MSC: | 54B10 | 
| MSC: | 54D20 | 
| MSC: | 54E18 | 
| idZBL: | Zbl 0804.54010 | 
| idMR: | MR1292590 | 
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| Date available: | 2009-01-08T18:09:29Z | 
| Last updated: | 2012-04-30 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/118648 | 
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