Multiple solutions for nonhomogeneous Klein–Gordon–Maxwell equations on R3

In this paper we study the following nonhomogeneous Klein–Gordon–Maxwell equations {−△u+V(x)u−(2ω+ϕ)ϕu=f(x,u)+h(x),in  R3,−△ϕ+ϕu2=−ωu2,in  R3. Under appropriate assumptions on VV, ff and hh, the existence of multiple solutions is proved via Variational methods.