Formulation and Evaluation of a Lactic Acid-Containing Serum for Facial Skin: Assessment of Efficacy and Safety - Ahmed, Najmuddin Mohammed; Naji, Ahmed Mohammed; Ahmed, Khattab Ali; Abdullah, Hamzah Ahmed; Ahmed, Youssef Abdullah; Abdo, Qassam Abdulkarim (University of Science and Technology, Sana’a, 2025)