Ivana Binic, Viktor Lazarevic, Milanka Ljubenovic, Jelena Mojsa, Dusan Sokolovic 2013, 'Skin Ageing: Natural Weapons and Strategies', Evidence-Based Complementary and Alternative Medicinehttp://dx.doi.org/10.1155/2013/827248. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)

Mohammad Adil, Syed Suhail Amin, Mohd Mohtashim 2018, 'N-acetylcysteine in dermatology', Indian Journal of Dermatology, Venereology and Leprologyhttp://www.ijdvl.com/article.asp?issn=0378-6323;year=2018;volume=84;issue=6;spage=652;epage=659;aulast=Adil. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)

Almudena Pérez-Sánchez, Enrique Barrajón-Catalán, María Herranz-López, Vicente Micol 2018, 'Nutraceuticals for Skin Care: A Comprehensive Review of Human Clinical Studies', Nutrientshttp://www.mdpi.com/2072-6643/10/4/403. Retrieved from DOAJ CC BY 4.0 (https://creativecommons.org/licenses/by-sa/4.0/legalcode)