Ding, Zhiying, et al. “Systemic Delivery of Allium Cepa L. Var Agrogatum Don Flavonoid-Rich Extract via the Percutaneous Route Using a Microemulsion System”. Asian Journal of Chemistry, vol. 25, no. 15, Sept. 2013, pp. 8727-31, doi:10.14233/ajchem.2013.15342.