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\bibitem{Mayer_etal2018} {\textquotedblleft}\textit{Optical enhancement of a printed organic tandem solar cell using diffractive nanostructures}{\textquotedblright}. Mayer JA, Offermans T, Chrapa M, Pfannm{\"o}ller M, Bals S, Ferrini R, Nisato G, Optics express \textbf{26}, A240 (2018).   http://doi.org/10.1364/OE.26.00A240

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