6Wedzicha JA. The heterogeneity of chronic obstructive pulmonary disease. Thorax, 2000, 55: 631-632.
7Standards for the diagnosis and care of patients with chronic obstructive pulmonary disease. American Thoracic Society. Am J Respir Crit Care Med, 1995, 152(5 Pt 2) : S77-121.
8Han MK, Agusti A, Calverley PM, et al. Chronic obstructive pulmonary disease phenotypes: the future of COPD. Am J Respir Crit Care Med, 2010, 182: 598-604.
9Gibson PG, Simpson JL. The overlap syndrome of asthma and COPD: what are its features and how important is it?. Thorax, 2009, 64: 728-735.
10Soler-Catalufia JJ, Cosio B, Izquierdo JL, et al. Consensus document on the overlap phenotype COPD-asthma in COPD. Arch Bronconeumol, 2012, 48: 331-337.