Bhatia, M., A. . jain, S. Dixit, and A. . Krishnan. “Higher GOLD Spirometeric Class (severity of Airflow Limitation) Correlated With Higher Number of Comorbidities”. Asian Journal of Medical Sciences, vol. 14, no. 12, Dec. 2023, pp. 234-8, doi:10.3126/ajms.v14i12.56801.