Lemma 3
Tag 09C2, permanent. Cite it as [Bourbaki, Tag 09C2].
Integration, chapter VI, § 3. Disintegration of measures
— Let T and X be two locally compact spaces with countable bases, a positive measure on T, and () a family of positive measures on X. If the mapping is scalarly -integrable (for the topology ), then the family is -adequate (, No. 1, Example).
For, Lemma 1, applied to , shows that the mapping is vaguely -measurable (, No. 5, Prop. 13).
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.