Clapp, Mónica, and Andrzej Szulkin. “Normalized Solutions to a Non-Variational Schrödinger System”. Topological Methods in Nonlinear Analysis 61, no. 1 (March 4, 2023): 445–464. Accessed July 22, 2024. https://apcz.umk.pl/TMNA/article/view/42924.