Example

Tag 0B07, permanent. Cite it as [Bourbaki, Tag 0B07].

General Topology, chapter I, § 2. Continuous functions

\* The mapping $f : x \to 1/(1 + x^2)$ of $\mathbf{R}$ into itself is continuous, but $f(\mathbf{R})$ is the half-open interval $]0, 1]$ , which is neither open nor closed in $\mathbf{R}$ . \*

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

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Cites

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