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\bibitem{Koester_etal2002} {\textquotedblleft}\textit{Doping of interfaces in (La$_{0.7}$Sr$_{0.3}$MnO$_{3}$)$_{1-x}$:(MgO)$_{x}$ composite films}{\textquotedblright}. K{\"o}ster S, Moshnyaga V, Samwer K, Lebedev OI, Van Tendeloo G, Shapoval O, Belenchuk A, Applied physics letters \textbf{81}, 1648 (2002).   http://doi.org/10.1063/1.1503849

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