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On accumulation points. (English) Zbl 0858.54008
The classes of topological spaces AC and AP, recently introduced by A. Pultr and A. Tozzi [ibid. 34, No. 3, 167-183 (1993; Zbl 0789.54008)] are investigated. Another class wAP is defined which in a certain sense lies between the two, and it is proved that these classes are proper and distinguished subclasses of Top. Finally, it is proved that neither AP nor wAP are productive.

MSC:
54B30 Categorical methods in general topology
Citations:
Zbl 0789.54008
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References:
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