mirza, M., N. Karim, W. B. kadri, and S. Asghar. “Clinical Efficacy of 1% Metformin Gel and Systemic Doxycyline in Chronic Periodontitis”. Journal of Liaquat University of Medical & Health Sciences, vol. 20, no. 3, Oct. 2021, pp. 204-8, http://ojs.lumhs.edu.pk/index.php/jlumhs/article/view/524.