“…And the maximal number of limit cycles in the vicinity of a Hopf singular point is a very challenging problem. 5 At present, most of the results obtained are concentrated on small limit cycles bifurcated from a focus on the local center manifold, for the general polynomial systems, see, eg, previous studies, 5,8,9 for Lotka-Volterra systems and chaotic systems, see, eg, Gyllenberg and Yan and Wang et al, 10,11 besides, in Liu et al, 12 six limit cycles are proved in Maxwell-Bloch system. Recently, Garcia et al 13 derive the theorems that bound the maximum number of limit cycles within the center manifold from any center at the origin, and the upper bounds on the cyclicity of the centers on center manifolds for the Lorenz, Chen and Lü families were given in Garcia et al, 14 clearly, the center bifurcation is more difficult to study.…”