“…For more recent literature about such Kirchhoff type problems we cite the works [2,27,16,15,8,13,32,31,5,4,30,21,28,22], which deal with the existence of solutions with various types of nonlinearities f and use mainly variational methods. Among them, we refer to [15,31,4,30,28,22] for considering also the case where the nonlocal term M is degenerate.…”