Bhatia, M., A. Sharma, B. Mishra, A. Thakur, V. Dogra, and P. S. Loomba. “Evaluation Of Charlson’s Co-Morbidity Index And Risk Factors Among Patients With And Without Extended Spectrum Î’-Lactamase Producing Enterobacteriaceae Spp. Urinary Isolates In A Super-Specialty Hospital: Evaluation Of Charlson’s Co-Morbidity Index And Risk Factors”. National Journal of Integrated Research in Medicine, vol. 7, no. 5, Jan. 2018, pp. 40-45, http://www.nicpd.ac.in/ojs-/index.php/njirm/article/view/1138.