“…C D/ jX z to the general fiber of f is klt (if .K X C / is not big we actually add a small ample to it). Then, supposing for simplicity that X and Y are smooth, and f regular, we invoke Campana's positivity result [Ca3], Theorem 4.13, to deduce that f .K X =Z C C D/ Q K Z is weakly positive. Then by results contained in [MM], [BDPP] and [N] the variety Z is forced to be either uniruled or to have zero Kodaira dimension.…”