Closure-preserving covers
نویسندگان
چکیده
منابع مشابه
SPACES WITH σ-WEAKLY HEREDITARILY CLOSURE-PRESERVING sn-NETWORKS
We prove that a space with a σ-weakly hereditarily closurepreserving sn-network is sn-first countable. As an application of this result, we prove that a Lindelöf space with a σ-weakly hereditarily closurepreserving sn-network is sn-second countable. The above results answer some questions posed by L. Yan. AMS Mathematics Subject Classification (2000): 54D20, 54D65, 54E20, 54E99
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ژورنال
عنوان ژورنال: Fundamenta Mathematicae
سال: 1974
ISSN: 0016-2736,1730-6329
DOI: 10.4064/fm-85-2-165-175