TAGHAVI, Mojgan and SHAHROKHI-DEHKORDI, Mohammad S. The existence of multiple topologically distinct solutions to $\sigma_{2,p}$-energy. Topological Methods in Nonlinear Analysis. Online. 31 December 2023. Vol. 62, no. 2, pp. 409 - 429. [Accessed 3 July 2024]. DOI 10.12775/TMNA.2023.010.