Khanduja, Divya, and Naveen Pandhi. “A Case Series on Asthma-COPD Overlap (ACO) Is Independent from Other Chronic Obstructive Diseases (COPD and Asthma)”. Journal of Pulmonology and Respiratory Research, vol. 5, no. 1, June 2021, pp. 054-8, doi:10.29328/journal.jprr.1001025.