ROOT::Math::Roots::Steffenson

class ROOT::Math::Roots::Steffenson : public ROOT::Math::GSLRootFinderDeriv

    private:

                                     Steffenson(const ROOT::Math::Roots::Steffenson&)
      ROOT::Math::Roots::Steffenson& operator=(const ROOT::Math::Roots::Steffenson&)

    public:

                                    Steffenson()
                            virtual ~Steffenson()

 usually copying is non trivial, so we make this unaccessible