Wang, Lixiong, Haibo Chen, and Senli Liu. “Existence and Multiplicity of Sign-Changing Solutions for a Schrödinger-Bopp-Podolsky System”. Topological Methods in Nonlinear Analysis 59, no. 2B (June 12, 2022): 913–940. Accessed April 19, 2024. https://apcz.umk.pl/TMNA/article/view/38707.