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\bibitem{Richard_etal1999} {\textquotedblleft}\textit{Room temperature and low-temperature structure of Nd$_{1-x}$Ca$_{x}$MnO$_{3}$ (0.3*x*0.5)}{\textquotedblright}. Richard O, Schuddinck W, Van Tendeloo G, Millange F, Hervieu M, Caignaert C, Raveau B, Acta crystallographica: section A: foundations of crystallography \textbf{55}, 704 (1999).   http://doi.org/10.1107/S0108767398012215

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