Sun, Juntao, and Tsung-fang Wu. “Existence and Multiplicity of Positive Solutions for a Schrodinger-Poisson System With a Perturbation”. Topological Methods in Nonlinear Analysis 46, no. 2 (December 1, 2015): 967–998. Accessed October 25, 2021. https://apcz.umk.pl/TMNA/article/view/TMNA.2015.079.