Abstract
For a real function f defined on a perfect Baire space X the following are equivalent: f is cliquish, and f is a pointwise limit of two monotone sequences of upper and lower quasi-continuous functions, respectively.
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Ewert, J. Characterization of Cliquish Functions. Acta Mathematica Hungarica 89, 269–276 (2000). https://doi.org/10.1023/A:1006762702077
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DOI: https://doi.org/10.1023/A:1006762702077