^Wu, M; Zhou, XJ; Konno, R; Wang, YX. D-dopa is unidirectionally converted to L-dopa by D-amino acid oxidase, followed by dopa transaminase.. Clinical and experimental pharmacology & physiology. 2006-11, 33 (11): 1042–6. PMID 17042912. doi:10.1111/j.1440-1681.2006.04484.x.