Corollary 1
Tag 09DZ, permanent. Cite it as [Bourbaki, Tag 09DZ].
Integration, chapter VII, § 1. Construction of a Haar measure
— Let K be a commutative locally compact field, E a finite-dimensional vector space over K, and u an endomorphism of the vector space E. Then .
If u is invertible, this follows from Prop. 15. If u is not invertible then , therefore .
Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.