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\bibitem{Cheng_etal2007} {\textquotedblleft}\textit{Single crystalline GaN grown on porous Si(111) by MOVPE}{\textquotedblright}. Cheng K, Degroote S, Leys M, van Daele B, Germain M, Van Tendeloo G, Borghs G, Physica status solidi: C: conferences and critical reviews \textbf{4}, 1908 (2007).   http://doi.org/10.1002/pssc.200674316

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