K. Tyagi, Y., Tyagi, S., G. Raj, H., & K. Gupta, R. (2010). In Vitro Antioxidant Activity Evaluation of 4-Methyl Coumarin Derivatives. Asian Journal of Chemistry, 22(5), 3622–3628. Retrieved from https://asianpubs.org/index.php/ajchem/article/view/11591