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Extension of Coverings, of Pseudometrics, and of Linear-Space-Valued Mappings

Published online by Cambridge University Press:  20 November 2018

Richard Arens
Richard Arens*
Affiliation:
University of California
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Let A be a closed subset of a topological space. We show that the following three conditions are equivalent.

1.1 Any countable neighbourhood-finite open covering of A (the topological terms referring to the relative topology of A) has a refinement which can be extended to be a countable neighbourhood-finite open covering of X.

Type
Research Article
Information
Canadian Journal of Mathematics , Volume 5 , 1953 , pp. 211 - 215
Copyright
Copyright © Canadian Mathematical Society 1953

References

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