منابع مشابه
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In [2], Arhangel’skĭı introduced the notion of ω-closed sets in relation to countable tightness. This paper deals with a class of sets called ω∗-closed sets and its topology which is stronger than the class of ω-closed sets due to Arhangel’skĭı. 2000 Mathematics Subject Classification: 54C10, 54D10.
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ژورنال
عنوان ژورنال: Czechoslovak Mathematical Journal
سال: 1956
ISSN: 0011-4642,1572-9141
DOI: 10.21136/cmj.1956.100214