What the conditions, other than DCT and MCT, under which $$\lim_{n\to\infty} \int f_n(x) \ \mathsf dx = \int lim_{n\to\infty} f_n(x) \ \mathsf dx\quad $$
where the $f_n$ are measurable functions?
DCT- Dominated Convergence Theorem MCT- Monotone Convergence Theorem