“…Another important problem concerns the global existence of smooth solutions when the parameters are fixed and the initial data are in a small neighborhood of the constant equilibrium state (1, 0, 0, B e ), which is a particular solution of system (2), where B e ∈ R 3 is any given constant. In [32] (see also [12,41,33]), the authors established a global existence result near such a constant equilibrium. This result did not take into account the dependence with respect to the parameters τ and γ.…”