How could I plot bifurcation for a nonlinear system using maple? For example I have the following nonlin. syst: x'=a*b*((x^2+c^2)/(x^2+1))-d*x y'=a*e*((y^3+f^3)/(x^3+1)*(g*x+1)-y for a, b c, d, e, f,g be given ; I want to get bifurcation by some parameter, e for instance.