@Article{ CinPra15, author = { Cinti, Eleonora and Pratelli, Aldo }, title = { Regularity of isoperimetric sets in $\mathbb R^2$ with density }, journal = { Math. Ann. }, year = { 2017 }, pages = { }, URL = { http://cvgmt.sns.it/paper/2659/ }, note = { cvgmt preprint} }