World Health Organization. Chronic obstructive pulmonary disease (COPD) Fact Sheet. https://www.who.int/news-room/fact-sheets/detail/chronic-obstructive-pulmonary-disease-(copd)
[2]
International Journal of Integrated Care. Earlier Diagnosis of Chronic Obstructive Pulmonary Disease (COPD). https://ijic.org/articles/10.5334/ijic.ICIC24251
[3]
PubMed - Biomedical Literature Database. https://pubmed.ncbi.nlm.nih.gov/