42 double _E = 1000.,
double _nu = 0.,
double _k = 0.,
double _beta = 0.);
43 Medium(
Problem &pbl, std::string
const &name, std::string _medium_name,
44 double _E = 1000.,
double _nu = 0.,
double _k = 0.,
double _beta = 0.);
47 virtual void write(std::ostream &out)
const override;