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\bibitem{Singh_etal2018} {\textquotedblleft}\textit{Zinc and iron concentration as affected by nitrogen fertilization and their localization in wheat grain}{\textquotedblright}. Singh BR, Timsina YN, Lind OC, Cagno S, Janssens K, Frontiers in plant science \textbf{9} (2018).   http://doi.org/10.3389/FPLS.2018.00307

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