CANDELA, Anna Maria and SPORTELLI, Caterina. Nontrivial solutions for a class of gradient-type quasilinear elliptic systems. Topological Methods in Nonlinear Analysis. Online. 12 June 2022. Vol. 59, no. 2B, pp. 957 - 986. [Accessed 22 July 2024]. DOI 10.12775/TMNA.2021.047.