Rajeev Kishore Saxena, et al. “Qualitative Assessment of Helicobacter Pylori by PCR in the Saliva of Male Smokers and Non-Smokers With Chronic Periodontitis”. Novel Research Aspects in Medicine and Medical Science Vol. 5, Oct. 2023, pp. 173-87, doi:10.9734/bpi/nramms/v5/6087C.