R. H. Perry, K. R. Brownell, K. Chingin, T. J. Cahill III, R. M. Waymouth, and R. N. Zare, “Transient Ru–Methyl Formate Intermediates Generated with Bifunctional Transfer Hydrogenation Catalysts,” Proc. Natl. Acad. Sci. USA 109, 2246-2250 (2012).