R. A. Faed and W. F. S. Badulla, “QUALITY AND SAFETY ASSESSMENT OF HERBAL ANALGESIC PREPARATIONS IN ADEN, YEMEN: HEAVY METAL AND MICROBIAL CONTAMINATION PERSPECTIVE”, Electron. J. Univ. Aden Basic Appl. Sci., vol. 7, no. 1, pp. 1–8, Mar. 2026.