EP1000913-A1  OVERS A ET AL: "Properties of the solid electrolyte gadolinia-doped ceria prepared by thermal decomposition of mixed cerium-gadolinium oxalate" JOURNAL OF THE AMERICAN CERAMIC SOCIETY, DEC. 1982, USA, Bd. 65, Nr. 12, Seiten 606-609, XP002098819 ISSN 0002-7820;  RAHAMAN M N ET AL: "EFFECT OF SOLID SOLUTION ADDITIVES ON THE SINTERING OF ULTRA-FINE CEO2 POWERS" JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, Bd. 15, Nr. 10, 1. Januar 1995, Seiten 939-950, XP000526624;  INABA H ET AL: "Sintering behaviors of ceria and gadolinia-doped ceria" SOLID STATE IONICS, Bd. 106, Nr. 3-4, 1. Februar 1998, Seite 263-268 XP004111881;  VAN HERLE J ET AL: "Sintering Behaviour and Ionic Conductivity of Yttria-Doped Ceria" JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, Bd. 16, Nr. 9, 1996, Seite 961-973 XP004047398EP1000913-B1  INABA H ET AL: "Sintering behaviors of ceria and gadolinia-doped ceria" SOLID STATE IONICS, Bd. 106, Nr. 3-4, 1. Februar 1998, Seite 263-268 XP004111881;  OVERS A ET AL: "Properties of the solid electrolyte gadolinia-doped ceria prepared by thermal decomposition of mixed cerium-gadolinium oxalate" JOURNAL OF THE AMERICAN CERAMIC SOCIETY, DEC. 1982, USA, Bd. 65, Nr. 12, Seiten 606-609, XP002098819 ISSN 0002-7820;  RAHAMAN M N ET AL: "EFFECT OF SOLID SOLUTION ADDITIVES ON THE SINTERING OF ULTRA-FINE CEO2 POWERS" JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, Bd. 15, Nr. 10, 1. Januar 1995, Seiten 939-950, XP000526624;  VAN HERLE J ET AL: "Sintering Behaviour and Ionic Conductivity of Yttria-Doped Ceria" JOURNAL OF THE EUROPEAN CERAMIC SOCIETY, Bd. 16, Nr. 9, 1996, Seite 961-973 XP004047398US6709628-B2  Journal of the American Ceramic Society, Bd. 65, No. 12, Dec. 1982-Title: Properties of the Solid Electrolyte Gadolinia-Doped Ceria Prpared By Thermal Decomposition of Mixed Cerium-Gadolinium Oxalate, By A. Overs et al.;  Journal of the European Ceramic Society, Bd. 15, Nr. 10, Jan. 1, 1995-Title: Effect of Solid Solution Additives on the Sintering of Ultra-Fine CeO Powders, By M.N. Rahaman et al.;  Journal of the European Ceramic Society, Bd. 16, Nr. 9, 1996, pp. 961-973-Title: Sintering Behaviour and Ionic Conductivity of Yttria-Doped Ceria, By Jan Van Herle et al.;  Solid State Ionics, Bd. 106, Nr. 3-4, Feb. 1, 1998, pp. 263-268-Title: Sintering Behaviors of Ceria and Gadolinia-Doped Ceria, By Hideaki Inabe et al.