Figure 6.

Three coexisting attractors with $\sigma =4$, $\delta =0.5$, $b=2$, $r=27$: (a,c,e) different perspectives on the coexistence of the chaotic and two stable fixed-point attractors for the initial values $(2,1,1,2)$ (blue), $(-2,1,1,-2)$ (red) and $(2,1,1,-2)$ (green); (b,d,f) the corresponding time series of the state variables $x_1$, $x_2$ and $x_4$, respectively.