@Misc{ ambfig07, author = { Ambrosio, Luigi and Figalli, Alessio }, title = { Geodesics in the space of measure-preserving maps and plans }, journal = { Arch. Rat. Mech. Anal. }, year = { 2007 }, pages = { }, URL = { http://cvgmt.sns.it/paper/1647/ }, note = { cvgmt preprint} }