Theorem 1
Tag 096A, permanent. Cite it as [Bourbaki, Tag 096A].
Integration, chapter V, § 7. Integration with respect to an induced measure
— Let g be a function defined on X, with values in or in a Banach space. For g to be essentially *-integrable, it is necessary* and sufficient that be essentially -integrable in (§ 5, No. 3, Example), in which case
This follows from Th. 2 of § 4.
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.