Abstract:A topological space is S-closed if and only if every semi-open cover of X has a finite subcollection whose closures cover X. The images of S-closed spaces under various mappings are investigated culminating in this main result: A Hausdorff space X is S-closed if and only if the irresolute image of X in any Hausdorff space is closed.
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- © Copyright 1977 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 66 (1977), 359-362
- MSC: Primary 54C10
- DOI: https://doi.org/10.1090/S0002-9939-1977-0451193-9
- MathSciNet review: 0451193