# Measurability of multifunction

Let $f:[a,b]\times \mathbb{R}^{n} \times \mathbb{R}^{m} \rightarrow \mathbb{R}^{n}$. Suppose $f (.,x, u)$ is Lebesgue measurable for each $(x,u)$. Suppose also that $f$ is continuous at $(x, u)$ for each fixed $t$.

Let $g: [a, b] \rightarrow [a, b]$ be a Lebesgue measurable function and $U: [a, b] \rightrightarrows \mathbb {R}^{m}$ be a Lebesgue measurable multifunction. Then the multifunction $$F(t,x) = f(g(t),x,U(t))$$ é $\mathcal{L}\times \mathcal{B}^{n}$-measurable (Lebesgue-Borel)? Or should require continuity in $t$ in the function $f$?

Obs: Let $H: \Omega \rightrightarrows \mathbb {R}^{n}$ and $(\Omega,\mathcal{F})$ be a measurable space. $H$ is $\mathcal{F}$-measurable if for each compact set $K \subset \mathbb {R}^{n}$, $$\{x \in \Omega: H(x) \cap K \not= \emptyset\} \in \mathcal{F}.$$

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What notion of measurability for multifunctions do you use? –  Michael Greinecker May 17 '13 at 22:27
Castaing-Valadier –  user78308 May 17 '13 at 22:30
This was crossposted to MO. In the future, please wait some time before posting your question in multiple fora, and when you do, provide links to the other posts - as you can imagine, it would be frustrating for someone to put time into answering your question here, only to see hear from you that you'd already gotten the solution elsewhere. –  Zev Chonoles May 18 '13 at 1:18
I asked this question in the mathoverflow also mathoverflow.net/questions/131012/measurable-multifunction –  user78308 May 18 '13 at 1:39