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Ulrich, A., M. Heyn, and A. Watts. Structure Determination of the Cyclohexene Ring of Retinal in Bacteriorhodopsin by Solid-state Deuterium NMR. 1992.

Ulrich, A., et al. Structure Determination of the Cyclohexene Ring of Retinal in Bacteriorhodopsin by Solid-state Deuterium NMR. 1992.