1. ^{{cite journal | vauthors = Sun L, Ruppert M, Sheludko Y, Warzecha H, Zhao Y, Stöckigt J | title = Purification, cloning, functional expression and characterization of perakine reductase: the first example from the AKR enzyme family, extending the alkaloidal network of the plant Rauvolfia | journal = Plant Molecular Biology | volume = 67 | issue = 5 | pages = 455–67 | date = July 2008 | pmid = 18409028 | doi = 10.1007/s11103-008-9331-7 }}
2. ^{{cite journal | vauthors = Rosenthal C, Mueller U, Panjikar S, Sun L, Ruppert M, Zhao Y, Stöckigt J | title = Expression, purification, crystallization and preliminary X-ray analysis of perakine reductase, a new member of the aldo-keto reductase enzyme superfamily from higher plants | journal = Acta Crystallographica. Section F, Structural Biology and Crystallization Communications | volume = 62 | issue = Pt 12 | pages = 1286–9 | date = December 2006 | pmid = 17142919 | pmc = 2225361 | doi = 10.1107/S174430910605041X }}