@Misc{ DegMaz19, author = { Degiovanni, Marco and Mazzoleni, Dario }, title = { Optimization results for the higher eigenvalues of the $p$-Laplacian associated with sign-changing capacitary measures }, journal = { J. London Math. Soc. }, year = { 2019 }, pages = { }, URL = { http://cvgmt.sns.it/paper/4309/ }, note = { cvgmt preprint} }