Benci, Vieri, Anna Maria Micheletti, and Daniela Visetti. 2001. “An Eigenvalue Problem for a Quasilinear Elliptic Field Equation on $\mathbb R^n$”. Topological Methods in Nonlinear Analysis 17 (2):191-211. https://apcz.umk.pl/TMNA/article/view/TMNA.2001.013.