text: #ifndef CTE_HPP
  #define CTE_HPP
  
  /*** Constantes ***/
  /***************************************/
  extern const double long hbar;
  extern const double long k_B;
  extern const double long m_e;
  extern const double long v_light;
  extern const double long Ry;
  extern const double long PI;
  /***********/
  
  #endif // CTE_HPP
  