WO200275749-A1  MEYER G: "Alkaline earth/rare earth halides and related systems" JOURNAL OF ALLOYS AND COMPOUNDS, ELSEVIER SEQUOIA, LAUSANNE, CH, vol. 303-304, May 2000 (2000-05), pages 409-415, XP004204396 ISSN: 0925-8388;  MORI T ET AL: "Improvement of the electrolytic properties of Y2O3-based materials using a crystallographic index" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 138, no. 3-4, 1 January 2001 (2001-01-01), pages 277-291, XP004228343 ISSN: 0167-2738;  SHIMURA T ET AL: "Proton conduction in non-perovskite-type oxides at elevated temperatures" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 143, no. 1, 1 June 2001 (2001-06-01), pages 117-123, XP004245339 ISSN: 0167-2738NL1018267-C2  MEYER G: "Alkaline earth/rare earth halides and related systems" JOURNAL OF ALLOYS AND COMPOUNDS, ELSEVIER SEQUOIA, LAUSANNE, CH, deel 303-304, Mei 2000 (2000-05), bladzijden 409-415, XP004204396 ISSN: 0925-8388;  MORI T ET AL: "Improvement of the electrolytic properties of Y2O3-based materials using a crystallographic index" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, deel 138, nr. 3-4, 1 Januari 2001 (2001-01-01), bladzijden 277-291, XP004228343 ISSN: 0167-2738;  SHIMURA T ET AL: "Proton conduction in non-perovskite-type oxides at elevated temperatures" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, deel 143, nr. 1, 1 Juni 2001 (2001-06-01), bladzijden 117-123, XP004245339 ISSN: 0167-2738;  SHIMURA T ET AL: "Proton conduction in non-perovskite-type oxides at elevated temperatures", SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 143, no. 1, 1 June 2001 (2001-06-01), pages 117 - 123, XP004245339, ISSN: 0167-2738;  MORI T ET AL: "Improvement of the electrolytic properties of Y2O3-based materials using a crystallographic index", SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 138, no. 3-4, 1 January 2001 (2001-01-01), pages 277 - 291, XP004228343, ISSN: 0167-2738;  MEYER G: "Alkaline earth/rare earth halides and related systems", JOURNAL OF ALLOYS AND COMPOUNDS, ELSEVIER SEQUOIA, LAUSANNE, CH, vol. 303-304, May 2000 (2000-05-01), pages 409 - 415, XP004204396, ISSN: 0925-8388EP1371067-B1  MEYER G: "Alkaline earth/rare earth halides and related systems" JOURNAL OF ALLOYS AND COMPOUNDS, ELSEVIER SEQUOIA, LAUSANNE, CH, vol. 303-304, May 2000 (2000-05), pages 409-415, XP004204396 ISSN: 0925-8388;  MORI T ET AL: "Improvement of the electrolytic properties of Y2O3-based materials using a crystallographic index" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 138, no. 3-4, 1 January 2001 (2001-01-01), pages 277-291, XP004228343 ISSN: 0167-2738;  SHIMURA T ET AL: "Proton conduction in non-perovskite-type oxides at elevated temperatures" SOLID STATE IONICS, NORTH HOLLAND PUB. COMPANY. AMSTERDAM, NL, vol. 143, no. 1, 1 June 2001 (2001-06-01), pages 117-123, XP004245339 ISSN: 0167-2738