Teng, Kaimin, and Ravi P. Agarwal. 2017. “Infinitely Many Solutions for a Class of Quasilinear Equation With a Combination of Convex and Concave Terms”. Topological Methods in Nonlinear Analysis 50 (1):299-332. https://apcz.umk.pl/TMNA/article/view/TMNA.2017.031.