Nguyen, Nghiem V. “Existence of Periodic Traveling-Wave Solutions for a Nonlinear Schrödinger System: A Topological Approach”. Topological Methods in Nonlinear Analysis 43, no. 1 (April 12, 2016): 129–155. Accessed April 27, 2024. https://apcz.umk.pl/TMNA/article/view/TMNA.2014.009.