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\bibitem{Roetter_etal2016} R{\"o}tter, R. P. A. U. -, J.H., Kassie, B. T., Paff, K., Palosuo, T. A. U. -, C.Y., Tao, F., Ewert, F., et al. (2016). Analysis of crop yield variability and yield gaps for maize and wheat in diverse climatic zones.. Berlin (Germany).

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