Existence of ground states for a Kirchhoff type problem without 4-superlinear condition

We consider the existence of ground state solutions for the Kirchhoff type problem −(a+b∫RN|∇u|2dx)△u+V(x)u=|u|p−2u,x∈RN,u∈H1(RN),where a,b>0, N=1,2,3 and 2