1. GOLDwww.goldcopd.org
2. [Guideline] Global Strategy for Diagnosis, Management, and Prevention of COPD: 2016. Global Initiative for Chronic Obstructive Lung Diseasehttps://goldcopd.org/global-strategy-diagnosis-management-prevention-copd-2016
3. Burden of COPDwww.who.int/respiratory/copd/burden
4. Chronic respiratory diseaseswww.who.int/respiratory
5. [Guideline] Institute for Clinical Systems Improvement. Diagnosis and Management of Chronic Obstructive Pulmonary Disease (COPD). 10th Edition. January 2016https://www.icsi.org/guidelines__more/catalog_guidelines_and_more/catalog_guidelines/catalog_respiratory_guidelines/copd/