“…Wu studied the existence of positive solutions, negative solutions, and sequence of high‐energy solutions for the following problem
in Li and Wu [
17] via a perturbation method when
and in Wu [
18] via a dual approach when
. Li [
19] considered the existence of positive solutions of problem () via variational methods where
and the nonlinear term is at critical growth, more precisely,
, where
. For the case
…”