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\bibitem{Maignan_etal1993} {\textquotedblleft}\textit{A new {\textquotedblleft}1212{\textquotedblright} mercury-based 90K superconductor: (Hg$_{1-x}$M$_{x}$)O$_{6+y}$}{\textquotedblright}. Maignan A, Van Tendeloo G, Hervieu M, Michel C, Raveau B, Physica: C : superconductivity \textbf{212}, 239 (1993)

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