Chen, Zhijie, Chang-Shou Lin, and Wenming Zou. “Infinitely Many Sign-Changing and Semi-Nodal Solutions for a Nonlinear Schrödinger System ”. ANNALI SCUOLA NORMALE SUPERIORE - CLASSE DI SCIENZE 15, no. special (February 25, 2016): 859-897. Accessed June 15, 2025. http://20.103.181.36/index.php/annaliscienze/article/view/443.