L-spaces in complete spaces of countable tightness using ♢
نویسندگان
چکیده
منابع مشابه
Products of ¿-spaces and Spaces of Countable Tightness
In this paper, we obtain results of the following type: if /: X -» Y is a closed map and X is some "nice" space, and Y2 is a &-space or has countable tightness, then the boundary of the inverse image of each point of Y is "small" in some sense, e.g., Lindelöf or «¿¡-compact. We then apply these results to more special cases. Most of these applications combine the "smallness" of the boundaries o...
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ژورنال
عنوان ژورنال: General Topology and its Applications
سال: 1978
ISSN: 0016-660X
DOI: 10.1016/0016-660x(78)90038-7