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Borel sets

The family F$ of Borel sets of a space S$ is the smallest family satisfying the conditions: (i) Every closed set belongs to F$; (ii) If X$ is in F$, then S \setminus X$ is in F$; (iii) The countable intersection of elements of F$ belongs to F$.
next up previous contents index
Next: branch point Up: Definitions Previous: bihomogeneous
Janusz J. Charatonik, Pawel Krupski and Pavel Pyrih
2001-11-30