Let $Q \subset R^n$ a box in $R^n$ (meaning $Q = [a_1,b_1]$ x ... x $[a_n,b_n]$). Let $f:Q \rightarrow [0,\infty ]$ be itegrable on $Q$.
Is the graph of the function $G=$ { $(x,f(x) | x \in Q$ } a Jordan set?
I managed to prove that $G$ is of measure $0$ using Darboux's sums. But is it also Jordan set? or is there an example where it isn't?