Example 1

Tag 0B33, permanent. Cite it as [Bourbaki, Tag 0B33].

General Topology, chapter I, § 5. Open mappings and closed mappings

Let $A$ be a subspace of a topological space $X$ . Then the canonical injection $j : A \to X$ is open (resp. closed) if and only if $A$ is open (resp. closed) in $X$ (§ 3, no. 1).

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

§ 3, no. 1