Comparison of effectiveness and safety of topical 30% metformin versus 4% hydroquinone in the treatment of epidermal melasma. J Pak Assoc Dermatol [Internet]. 2024 May 6 [cited 2026 Jul. 27];34(1):73-9. Available from: https://www.jpad.com.pk/index.php/jpad/article/view/2748