Abdulhameed, S. S., and H. T. Nanakaly. “Effect of Non Surgical Periodontal Treatment on TNF-α Levels in Serum of Patients With Chronic Periodontitis”. Zanco Journal of Medical Sciences (Zanco J Med Sci), vol. 20, no. 1, Apr. 2016, p. 1167_1174, doi:10.15218/zjms.2016.0005.