One sees that different from the cases of Einstein gravity and Gauss–Bonnet gravity, (38)is not an equation of a single func-tion, since f(r)enters the equation through R. Furthermore, it is a high order equation after substituting Rinto (38). Principally, we can use the first perspective (Einstein interpretation) to obtain the equation of κ. And we then use the associated equations of (38)and κto find the two functions h(r)and f(r). However, it is hard to find the analytical solutions in this way.