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2. Prevalence of COPD in Spain: impact of undiagnosed COPD on quality of life and daily life activities

3. Grupo de Trabajo de GesEPOC. Guía de Práctica Clínica para el Diagnóstico y Tratamiento de Pacientes con Enfermedad Pulmonar Obstructiva Crónica (EPOC) – guía Española de la EPOC (GesEPOC). Versión 2017 [Clinical Practice Guideline for the Diagnosis and Treatment of Patients with Chronic Obstructive Pulmonary Disease (COPD) – Spanish Guideline for COPD (GesEPOC). 2017 version]. Arch Bronconeumol. 2017;53(Suppl 1):2–64. Spanish.

4. Global Initiative for Chronic Obstructive Lung Disease (GOLD). From the global strategy for the diagnosis, management and prevention of COPD. 2017. Available from: http://goldcopd.org. Accessed March 16, 2020.