Holmstrom Jouanolou's trick

This might refer to the fact that for any quasiprojective variety $X$, there exists an affine bundle $X' \to X$ such that $X'$ is affine. For this fact, see Bloch and Esnault: Lectures on algebro-geometric Chern-Weil…

http://mathoverflow.net/questions/7374/the-jouanolou-trick

nLab page on Jouanolou's trick