Figure 1From: Bogdanov–Takens bifurcation of a Holling IV prey–predator model with constant-effort harvestingThe phase portraits for system (1.2). (a) \(E_{0}\) is a sink if \(a=0.2, \beta =0.8,\delta =0.3, h_{1}=0.4\) and \(h_{2}=0.6\); (b) \(E_{0}\) is a saddle if \(a=0.2, \beta =0.8,\delta =0.9, h_{1}=0.4\) and \(h_{2}=0.6\)Back to article page