POVRAY produced images and simulation based on paper by R. Gilmore, Two-parameter families of strange attractors, Chaos 17, 013104 (2007). See http://www.physics.drexel.edu/~tim/programs/twoparam for program details regarding one example from which all simulations can be formed. Two sets are below--use the bottom scroll bar to see them all (van der Pol, Duffing).  Simulations by Timothy Jones (based on above). For simulations along these lines for the Rossler attractor, see Dr. Gilmore's entry:  http://lagrange.physics.drexel.edu/flash/twistross/
	van der Pol DX=b*Y + (c-d*Y*Y)*X; DY=-X+A*sin(w*t); (a,b,c,d,w,T)=(0.25,0.7,1.0,10.0,PI/2,4.0)	Duffing  DX = Y;  DY = -del*Y - X * X * X + X +a* sin(w*t); (a,del,w,T)=(0.4,0.4,1.0,2*PI);
k=-2
k=-1
k=0
k=1
k=2