Let $M = (\mathbb{R}^N, \mathcal{L}, \ell)$ be a D1744: Lebesgue measure space such that

(i)	$f : \mathbb{R}^N \to \mathbb{C}$ is a D5617: Complex Borel function on $M$

Let $a \in \mathbb{R} \setminus \{ 0 \}$ be a D993: Real number.

Then \begin{equation} \int_{\mathbb{R}^N} f(x / a) \, \mu(d x) = |a|^N \int_{\mathbb{R}^N} f(x) \, \mu(d x) \end{equation}