@Misc{ BucFra14, author = { Bucur, Dorin and FragalĂ , Ilaria }, title = { A Faber-Krahn inequality for the Cheeger constant of N-gons }, journal = { Journal of Geometric Analysis }, year = { 2014 }, pages = { }, URL = { http://cvgmt.sns.it/paper/2352/ }, note = { cvgmt preprint} }