Ukrainian Mathematical Journal

, Volume 71, Issue 6, pp 912–920 | Cite as

Discontinuity Points of Separately Continuous Mappings with at Most Countable Set of Values

  • V. K. Maslyuchenko
  • O. I. FilipchukEmail author

We obtain a general result on the constancy of separately continuous mappings and their analogs, which yields the well-known Sierpiński theorem. By using this result, we study the set of continuity points of separately continuous mappings with at most countably many range of values including, in particular, the mappings of the square of Sorgenfrey line into the Bing plane.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Fed’kovych Chernivtsi National UniversityChernivtsiUkraine

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