Recent Google Chrome update (8.x) introduced Google's own PDF viewer and it's enabled by default. They say it is more secure and always up-to-date, but it does lack some functionality.

You can disable the plugin by visiting about:plugins or chrome://plugins page and choosing to disable the Chrome PDF Viewer plugin. Which, at least for me, reverted the handling of PDFs to the pre-update state.

How can I enable the PDF bar in Google Chrome?
"Lebesgue's Theorem" states that for any bounded $f:[a,b] \to \mathbb{R}$, $f$ is Riemann Integrable iff $m\{x:f  \text{ is not continuous at x }\}=0$, and if so Riemann's integral coincides with Lebesgue's. ($m$ is Lebesgue's measure).

Does there exist a generalization of this theorem for higher dimensions? Can I have a proof or a reference please?
