“…Various nonlinear analysis theories and methods may be used to study the
‐Hessian equation, such as the spaces theories [
12–21], smoothness theories [
22–27], operator theories [
28–31], fixed point theorems [
32–36], sub‐super solution methods [
37–39], monotone iterative techniques [
40, 41], and the variational method [
42–44]. For example, by adopting the sub‐super solution method, Zhang et al [
37] recently established the interval of the eigenvalue in which the existence of solutions for the following singular augmented
‐Hessian equation is guaranteed
where
,
…”