Corollary
Tag 0C96, permanent. Cite it as [Bourbaki, Tag 0C96].
General Topology, chapter IX, § 6. Polish spaces, Souslin spaces, Borel sets
If a countable partition of a metrizable space is formed of Souslin sets, then these sets are Borel sets. In particular, every Souslin set in a metrizable space, whose complement is a Souslin set, is a Borel set.
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.
Cited by
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Cites
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