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Schmid, Markus B.; Zeitler, Kirsten; Gschwind, Ruth M.. (2011). NMR Investigations on the Proline-Catalyzed Aldehyde Self-Condensation: Mannich Mechanism, Dienamine Detection, and Erosion of the Aldol Addition Selectivity. , 76(9), 3005–3015. doi:10.1021/jo200431v 
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