Azizi, T. et al. 2019. Prevalence of Periodontal Disease in Type 2 Diabetic Patients with and without Vitamin D Deficiency. Regeneration, Reconstruction & Restoration (Triple R). 4, 3 (Jul. 2019), 113–116. DOI:https://doi.org/10.22037/rrr.v4i3.29314.