crystal structure of lanthanoidoxides Ln<sub>2</sub>O<sub>3</sub>, A Type (hexagonal)
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Eigenes Werk (own work), data source: M. Faucher, J. Pannetier, Y. Charreire and P. Caro: <i>Refinement of the Nd2O3 and Nd2O2S structures at 4 K</i>. In: Acta Cryst. (1982). B38, 344-346.