Garagnani, Elisa, and Francesco Uguzzoni. “A Multiplicity Result for a Degenerate Elliptic Equation With Critical Growth on Noncontractible Domains”. Topological Methods in Nonlinear Analysis 22, no. 1 (September 1, 2003): 53–68. Accessed July 8, 2025. https://apcz.umk.pl/TMNA/article/view/TMNA.2003.027.