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Czechoslovak Mathematical Journal

, Volume 57, Issue 4, pp 1223–1237 | Cite as

LJ-spaces

  • Yin-Zhu Gao
Article
  • 40 Downloads

Abstract

In this paper LJ-spaces are introduced and studied. They are a common generalization of Lindelöf spaces and J-spaces researched by E. Michael. A space X is called an LJ-space if, whenever {A, B} is a closed cover of X with AB compact, then A or B is Lindelöf. Semi-strong LJ-spaces and strong LJ-spaces are also defined and investigated. It is demonstrated that the three spaces are different and have interesting properties and behaviors.

Keywords

LJ-spaces Lindelöf J-spaces L-map (countably) compact perfect map order topology connected topological linear spaces 

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Copyright information

© Mathematical Institute, Academy of Sciences of Czech Republic 2007

Authors and Affiliations

  1. 1.Department of MathematicsNanjing UniversityNanjingP. R. China

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