Saleh, S. M. K., O. A. AbdulGhani, and F. M. Al-Hariri. “Assessment on Hydroquinone Levels Insome Skin Lightening Creams Available in Aden Markets, Yemen”. University of Aden Journal of Natural and Applied Sciences, vol. 19, no. 2, Aug. 2015, pp. 355-63, doi:10.47372/uajnas.2015.n2.a09.