EN
Phase equilibria in Gd_2O_3-CeO_2-CuO system were studied based on samples obtained from appropriate mixtures of the starting components, prepared by a conventional solid state reaction in air. The phase relations prevalent in this system have been deduced based on X-ray diffraction of well-equilibrated samples. An isothermal cross-section diagram through the system at 980°C is presented and chemical constitution of the Ce-doped Gd_2CuO_4 phase is proposed.