Wathoni, Nasrul, Sriwidodo, and Panji Luhur M. 2012. “Effect of Iontophoresis and Propylene Glycol on the in Vitro Diffusion of Ethyl Vitamin C Cream ”. International Research Journal of Pharmaceutical and Applied Sciences 2 (4), 31-34. https://scienztech.org/index.php/irjpas/article/view/316.