Chaotic attractors

The Lorenz system $\dot x=\sigma(y-x),\ \dot y=x(\rho-z)-y,\ \dot z=xy-\beta z$ with $\sigma=10,\ \rho=28,\ \beta=8/3$.

The Rössler system $\dot x=-y-z,\ \dot y=x+ay,\ \dot z=b+z(x-c)$ ($a=b=0.2,\ c=5.7$).