Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsHopf Bifurcation in a Biased van der Pol Oscillatorhttp://demonstrations.wolfram.com/HopfBifurcationInABiasedVanDerPolOscillator/]]>http://demonstrations.wolfram.com/HopfBifurcationInABiasedVanDerPolOscillator/Effect of a Perturbation on the Stable Points of a Dynamical Systemhttp://demonstrations.wolfram.com/EffectOfAPerturbationOnTheStablePointsOfADynamicalSystem/]]>http://demonstrations.wolfram.com/EffectOfAPerturbationOnTheStablePointsOfADynamicalSystem/Egg-Shaped Orbits of Non-Uniform Oscillatorshttp://demonstrations.wolfram.com/EggShapedOrbitsOfNonUniformOscillators/]]>http://demonstrations.wolfram.com/EggShapedOrbitsOfNonUniformOscillators/