Wolfram Demonstrations Projecthttp://demonstrations.wolfram.com/An Open Resource of Interactive Mathematica VisualizationsCopyright 2009 Wolfram Demonstrations Project & ContributorsBolzano's Theoremhttp://demonstrations.wolfram.com/BolzanosTheorem/]]>http://demonstrations.wolfram.com/BolzanosTheorem/Fermat's Theorem on Stationary Pointshttp://demonstrations.wolfram.com/FermatsTheoremOnStationaryPoints/]]>http://demonstrations.wolfram.com/FermatsTheoremOnStationaryPoints/